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Is it possible for a human to get rabies from a rabies vaccine meant for dogs?

Is it possible for a human to get rabies from a rabies vaccine meant for dogs?


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What would happen if a human was injected with a rabies vaccine meant for dogs? I know vaccines can contain weak or dead strains of the virus, but is it possible that the human could become infected with rabies from a vaccine meant for dogs? My thinking is that maybe a dogs' immune system is more suited to deal with a weak strain of rabies that would otherwise infect a human.


It would depend on which vaccine you're talking about, as there are several. Some use attenuated strains of the Rabies virus, others use killed, and some are recombinant glycoprotein vaccines. Here is a list from the CDC of all the rabies vaccines available in the US in 2011 (I wasn't able to find anything newer). Generally speaking, through, one would expect the FDA in the US and the relevant authorities in other companies to require vaccine manufacturers show that their product is safe in other species, in case of accidental exposure, such as you are talking about here. This is especially true of something being given to an animal that is quite often a family pet.

If you think you've been exposed to any type of medication which has not been prescribed for you, including dog rabies vaccine, you should seek medical attention immediately, if not sooner, but based on my experience in the pharmaceutical industry and dealing with regulatory agencies, you should be pretty safe, as the regulations surrounding vaccines are quite stringent.


Vaccination schedules

Vaccination of dogs, ferrets, and livestock can be started at no sooner than three months of age. Some cat vaccines can be given as early as two months of age. Regardless of the age of the animal at initial vaccination, a booster vaccination should be administered one year later.

Dogs, Cats, and Ferrets

All dogs, cats, and ferrets should be vaccinated and revaccinated against rabies according to product label directions. If a previously vaccinated animal is overdue for a booster, it should be revaccinated. Immediately following the booster, the animal is considered currently vaccinated and should be placed on a vaccination schedule according to the labeled duration of the vaccine used.

Livestock

Consideration should be given to vaccinating livestock that are particularly valuable. Animals that have frequent contact with humans (e.g., in petting zoos, fairs, and other public exhibitions) and horses traveling interstate should be currently vaccinated against rabies.

Confined Animals

No parenteral rabies vaccines are licensed for use in wild animals or hybrids (i.e., the offspring of wild animals crossbred to domestic animals). The AVMA has recommended that wild animals or hybrids should not be kept as pets (14&ndash17).

Maintained in Exhibits and in Zoological Parks

Captive mammals that are not completely excluded from all contact with rabies vectors can become infected. Moreover, wild animals might be incubating rabies when initially captured therefore, wild-caught animals susceptible to rabies should be quarantined for a minimum of 6 months. Employees who work with animals at exhibits and in zoological parks should receive preexposure rabies vaccination. The use of pre- or postexposure rabies vaccinations for handlers who work with animals at such facilities might reduce the need for euthanasia of captive animals that expose handlers. Carnivores and bats should be housed in a manner that precludes direct contact with the public (12).


What counts as a medical exemption

Here’s where things start to get a little more complex. “[Doctors] have a very standard list as to what should and shouldn’t be considered a medical contraindication to vaccination,” Dr. Orenstein says. This list is put together by the Advisory Committee on Immunization Practices (ACIP), a committee within the CDC, and issued in conjunction with the American Academy of Pediatrics (AAP) and the American Academy of Family Physicians (AAFP). Its goal is to best protect children’s health across the United States.

For example, a contraindication for most commonly used vaccines is the extremely rare instance that someone has had a “severe allergic reaction (e.g., anaphylaxis) after a previous dose or to a vaccine component,” per the ACIP. Someone having a severe allergic reaction to a vaccine (which can happen with any medication) only happens in an estimated one in a million doses.

As another example, a contraindication for vaccines such as MMR (measles, mumps, rubella) or varicella (chicken pox) is if someone has severe immunodeficiency, which can be caused by something like HIV, a treatment like chemotherapy, or long-term immunosuppressive therapy, according to the ACIP. Severe immunodeficiency is basically the only time it’s possible for a vaccine—and even then only a live, attenuated vaccine—to give someone the illness it’s meant to protect against, like measles or chicken pox. Live, attenuated vaccines use alive but extremely weak versions of the pathogen in question rather than dead versions. This won’t make a person with a typically functioning immune system sick, but if someone’s immune system is very weak, doctors often don’t want to take that chance.

Then there are various precautions for vaccination, which can fall into a few different buckets.

One is if the vaccine may increase the child’s risk of a serious adverse reaction, but less so than a contraindication would, according to the ACIP. An example is how having an egg allergy that has caused breathing problems in the past is a precaution for flu vaccination because most flu vaccines are made through an egg-based process. That doesn’t mean a child with this type of egg allergy automatically shouldn’t get vaccinated for the flu, the CDC explains. Remember those one-in-a-million odds of a severe allergic reaction to a vaccine? Skipping the flu vaccine in this case wouldn’t be warranted. Instead, it means that a child with this type of allergy should get vaccinated for the flu by a health-care provider who has good knowledge of allergic reactions, just in case.

Another overarching precaution is if you're sick with something else at the time—even just a mild cold. The reason for this is because doctors don't want you to think that your illness symptoms were caused by the vaccine. Like any other medication, vaccines can sometimes cause mild side effects that typically go away all on their own (like a low-grade fever, a rash, and swelling of neck glands). It can be easy to misattribute these symptoms to an unrelated illness or vice versa. For this reason “moderate or severe acute illness with or without fever” is a precaution for all vaccines, according to the ACIP.

This is a great example of how medical exemptions can get a little hazy. Although there’s a standard list of contraindications and precautions for vaccination, sometimes there’s ambiguity in the language that can leave room for interpretation. The “moderate or severe acute illness” precaution for vaccination doesn’t actually define the moderate or severe acute illnesses in question. It also doesn’t say how long a health-care provider should consider delaying a vaccine in this case—only that the person can get vaccinated after they have been screened for contraindications and their acute illness has improved.

“There’s room for clinical judgment there,” Daniel Salmon, Ph.D., M.P.H., professor at the Johns Hopkins Bloomberg School of Public Health and director of the Institute for Vaccine Safety at the Johns Hopkins Bloomberg School of Public Health, tells SELF.

This isn’t necessarily a bad thing “if the doctor is well-informed in the science and [writes medical exemptions] consistent with the science,” Salmon says. But it does create an opportunity for some vaccine-hesitant parents to get unnecessary medical exemptions for their children, ultimately putting their kids and others at risk of illness or even death.


Some animals can get aggressive when infected with rabies, but that’s not always the case.

A rabid coyote that attacked a North Carolina man last April had been reportedly aggressive and ferocious, as was a stray cat that was thought to have rabies after it was aggressive and pounced on a 3-year-old girl last summer, also in North Carolina.

But with bats who are ill with rabies, for example, while they do behave strangely, it’s often in ways that allow humans to interact with them. They may be awake during the daytime, or on the ground instead of flying. Rohde points out that about 10 percent of “downed” bats, meaning they are unable to fly properly, are rabid. “So about a one in 10 chance, which isn’t great odds if you’re picking things up,” Rohde says.

Unfortunately, there are no good tests for rabies in animals, other than observing them for a period to see if they exhibit classically rabid behavior (which you can’t do if the animal is wild and can’t be tracked). Diagnosis is done after death, by testing the brain.


The immune response to rabies virus infection and vaccination

Infection with rabies virus causes encephalitis in humans that has a case fatality rate of almost 100%. This inability to resolve infection is surprising since both pre-exposure vaccination and, if given promptly, post-exposure vaccination is highly effective at preventing encephalitic disease. The principal immunological correlate of protection produced by vaccination is neutralizing antibody. T-helper cells contribute to the development of immunity whereas cytotoxic T cells do not appear to play a role in protection and may actually be detrimental to the host. One reason for a failure to protect in humans may be the poor immunological response the virus provokes, despite the period between exposure to virus and the development of disease being measured in months. Few individuals have measurable neutralizing antibody on presentation with disease, although in many cases this develops as symptoms become more severe. Furthermore, when antibody is detected in serum it rarely appears in cerebrospinal fluid suggesting limited penetration into the CNS, the site where it is most needed. The role of the modest mononuclear cell infiltrate into the brain parenchyma is unclear. Some studies suggest the virus can suppress cell-mediated immunity early during the infection although there is little mechanistic evidence to support this beyond suppression of intracellular interferon production by the viral phosphoprotein. In contrast, levels of antibody in the CNS correlate to the peak virus production within the CNS. Here we review the current understanding of immune responses to rabies infection and vaccination against this disease. This article identifies a need to understand how rabies antigens are initially presented and how this can influence the subsequent development of antibody responses. This could help identify ways in which the response to prophylactic vaccination can be enhanced and how the natural immune response to infection can be boosted to combat neuroinvasion.


How a handful of veterinarians saved millions of human lives and eradicated a disease from the Earth

On May 25, 2011, the International Organization of Epizootics (OIE), something like the WHO of veterinary medicine, declared eradicated an infectious disease that killed millions of animals and also ended the lives of millions of human beings.

This article has been conceived to show that animal health and human well-being are intimately connected. Also to share the history of a terrible disease that caused enormous suffering, to narrate the global race that led to its eradication and, finally, as a tribute to those that made this feat possible.

Today, rinderpest along with smallpox are the only two infectious diseases eradicated worldwide. Let’s hope polio soon is next.

I would like to start with a travel back in time: Rome A.D. 1713:

Nothing could appease Pope Clement XI. The recent signing of the Treaty of Utrech had caused him to lose territories and influence. France, with the Jansenist heresy and its king, that arrogant Louis XIV did nothing but give him headaches.

All this, although annoying, fell within the logic of the struggle for power. Something much more serious was keeping the Bishop of Rome awake. It was not sin or the works of the evil one that tormented him but something much more prosaic: his cattle were dying. Not even the procession to St. Peter’s Basilica, followed with zeal by the faithful, who also lost their animals, gave the expected results. The Lord seemed to have turned his back on him. 1714 began with the worst omens, the cold did not contain the epidemic and the fields were covered with dead animals. Hunger lurked. There was no milk, no meat, and much worse: no animals to plow the fields. Without them it was impossible to cultivate the land and obtain crops. As the year progressed, their losses were approaching 25,000 head: a catastrophe.

So, the Supreme Pontiff, to save his flocks, put his trust in the same person who took care of his health. His personal physician: Giovani Maria Lancisi.

Portrait of Giovani Maria Lancisi. The Pope’s physician

The doctor put to work and obtained the papal favor to – against the criteria of many cardinals – promulgate a series of norms among which the following consideration stood out:

“It is better to kill all the sick and suspicious animals, rather than allow the disease to spread in order to have enough time and the honor to discover a specific treatment that is often sought without success.”

To the sacrifice of all sick animals and those that had been in contact with them, he added a strict control of the movements of livestock (and other animals such as dogs) as well as the obligation to bury the corpses in quicklime and not take advantage of anything, skin nor meat, to avoid future infections.

In addition, those who did not comply with these norms paid it well with the punishment of galleys in perpetuity (if they were ecclesiastical) or were directly executed (all others). There were no exceptions of degree, social class or economic position.

In nine months, the epidemic was under control.

The success of the Italian doctor did not go unnoticed in the European courts and his standards were imposed in much of the continent. He also served to lay the foundations for the study of the principles that had controlled the epidemic and that resulted in the creation of the world’s first veterinary college, founded in the French city of Lyon in 1761 with the royal support of Louis XV.

Royal document of approval of the first veterinary college in the world. Lyon France 1761

Although in a very timid way, the rulers began to realize that this evil could not be overcome without cross-border collaboration. Historical enemies would have to work together to fight this cattle plague.

Today we know that the disease that ruined Pope Clement XI’s finances was cattle plague (also known by its German name of Rinderpest). A highly contagious and highly deadly virus (over 90%) that preyed on both domestic and wild ruminants. It arrived in Europe with the Asian armies and it was, later, the local armies that spread the infection since the logistics and transport of war materials made it necessary to use the traction force of the oxen who, together with the weapons, carried the infection. With the arrival of the railroad, the cattle trade grew exponentially and with it the transmission of the virus accelerated throughout the continent, arriving in waves mainly from Russia, where it was endemic.

The virus belongs to the genus of morbilliviruses such as canine distemper or measles. The latter appeared as a Rinderpest mutation that was adapted to humans around the 11th or 12th century AD. It is a highly contagious RNA virus. After infection, the animal began to show the first symptoms 3-6 days later: fever, lethargy, nasal and eye discharges, mouth sores and a foul odor. Later, diarrhea appeared, and the animal died a few days afterwards.

Symptoms of the disease and an actual photo of ocular discharge

The high animal mortality became a death sentence for the communities. Without cattle, milk and meat were lacking. But worse still, the driving force that allowed the fields to be plowed disappeared without oxen, it was the people who had to tie themselves to the plows and drag them to try to obtain a meager harvest, always insufficient. Those who could afford it bought horses or mules – immune to the disease – but high demand drove prices up.

Thus, in the successive epidemics that have been documented in the England of the SXIV, a draft horse went from a cost of 12 shillings to 35 in full epidemic. Hunger reached the villages, and it was not uncommon that hunger pushed people to eat carrion and even to commit acts of cannibalism.

Horse prices sharp increased in impacted communities. It took years to bring prices back to normal

Rinderpest accelerated historical events of first magnitude. Thus in 1749 the French physician Blondet described the situation in the countryside of his country: “desolate pastures, uncultivated lands, abandoned farms, everything testifies to our misfortune.” In the Limousin region alone, 4,000 people died of hunger in March 1770. In addition to the mortality caused by the disease, there were also the shots that the soldiers had been ordered to fire on any animal suspected of having been in contact with sick cattle. Although the king paid for the shot animals, the new prices of healthy cattle, always on the rise, made the royal compensation worthless. With no ploughing force, no manure, and without key food sources, it is not surprising that spirits were stirred and that discontent, as some historians point out, contributed to the breeding ground that led to the French Revolution in 1789.

Without oxen, people had to plough the fields. Exhausting work to obtain poor results

The horror was not limited to Europe, Africa suffered the plague as a result of successive imports of European cattle. At the end of the 19th century, the Ethiopian Emperor Menelik lost more than 250,000 cattle. Thus began the great Ethiopian famine of 1888-1892, which a French missionary described as follows: “wherever I go I come across walking skeletons or corpses half-eaten by hyenas, of the hungry who have fallen from exhaustion.”

One third of the Ethiopian population died because of this famine.

But not only domestic livestock were involved. Wild animals also suffered from the disease: buffalo, giraffe, antelope, all ungulates fell prey to the infection.

Livestock is deeply rooted in many African cultures for which animals are the only way to have capital, cattle constitute an economic system in themselves: dowries, inheritances and loans are paid with livestock. Animals’ death meant the death of entire cultures.

Cattle plague deaths in South Africa

Something had to be done and a good number of countries came to an agreement to put aside their quarrels and try to join forces and fight this disease.

In 1871, the Austrian government launched the first international conference for rinderpest control. Governments agreed to alert each other by telegraph when there was an outbreak of disease to interrupt the trade in animals, they promised to compensate farmers for their losses, as well as to implement stringent disinfection measures in the event of any positive diagnosis.

Following these rules, the German authorities alerted their British counterparts – in 1877 – that the animals that had just arrived in their territory from Hamburg could be contaminated as in the German city an outbreak of rinderpest had just been diagnosed. Rapid communication enabled English veterinarians to immobilize and slaughter the cows, and prevent the disease from spreading across English territory. The immobilization of German animals was quickly established, as well as the prohibition of importation into Dutch, Belgian, Swiss and French territory, among others. The efforts made it possible to stop the disease in Europe.

But although the virus saw its expansion in the old continent short-circuited, it began its wide expansion in other latitudes thanks to the colonizing activity of the European powers.

As an example, the importation of cattle to feed the Spanish military contingent located in the Philippine Islands introduced Rinderpest in the archipelago. But where the virus was rampant was on the African continent. In South Africa, the plague preyed on cattle and no preventive measure seemed to work. So serious was the situation that the government of the Cape province requested the services of Robert Koch who years before had established his famous postulates that allowed a disease to be attributed to a specific germ. Koch knew his trade and was certain that a micro-organism caused the plague. Vaccination experiences against rabies and smallpox made him optimistic about finding an effective prophylaxis against rinderpest.

After many tests with different body fluids, he ended up recommending that healthy cattle be inoculated with bile from animals that had died of the disease. The method was unsuccessful, but it allowed local scientists to create another alternative: injecting serum from infected animals. It was not an ideal solution, many other infections were transmitted trying to avoid the plague, but the inoculated animals developed some immunity against the virus. Mortality in treated cattle dropped from 77% to 44%. Colons of European origin had more access to this remedy and inoculated more, hence we can know the difference between cattle that did not receive prophylaxis -mainly from native cattlemen- versus those of owners of European origin.

In 1902, Turkish researchers proved that the agent behind plague outbreaks was a virus.

A few years later, in 1910, the Japanese invaded the Korean peninsula and Japanese veterinarians set out to create an immune belt between Korea and China to protect the Korean herd from rinderpest. To do this, the veterinarian Chiharu Kakizaki was able to inactivate the viral agent in blood and spleen samples by mixing them with glycerin: The first vaccine against rinderpest was born.

International coordination efforts to fight the plague took another big step with the signing of 28 countries for the creation, in 1928, of the OIE, the International Organization of Epizooties, still active today and which played a leading role, together with the FAO, in eradicating the rinderpest from the Earth.

A few years later, in the Philippines, an American military veterinarian, Raymond Alexander Kesler, used chloroform to inactivate the virus present in macerated spleen, lymph nodes and liver. The vaccine required multiple doses and provided immunity for a limited period of time, but the important thing was that it helped, along with quarantine and slaughter measures, to limit the disease. The Philippines launched a vaccination campaign that between 1924-1931. It was administered at a rate of 300,000 heads/year.

Dead vaccines do not cause infection because the virus is inactive, but they are capable of “alerting” the immune system and generating defenses. The major drawback is the need to repeat the doses to maintain their prophylactic capacity, which is often prohibitively expensive and labor intensive.

The next battle was to get live vaccines, which could stimulate long-term immunity without causing the disease or led to an attenuated form, with mild symptoms. Previous experiences with rabies virus and smallpox invited to test the attenuation of the virus by passage in non-target species. Thus, it was tested on different animals with varying success. The first successful experience was obtained by passing in goats and gave rise to the vaccine called Kabete O, very effective for African cattle (although it produced a mild disease) but still fatal for 50% of the European herd, so the the old continent should continue with the administration of the dead vaccine.

Kabete O could easily be transported in previously immunized live goats. Once slaughtered, between 500 and 800 doses could be obtained from each goat. It was a tremendously efficient mode of transport in the conditions of the African continent.

We thus arrive in the 1940s. Quite surprisingly, the Second World War was, de facto, a boost in the fight against rinderpest.

American President Roosevelt knew firsthand the consequences of an infection. At the age of 40, he suffered a paralysis that he would live with for the rest of his life. Polio preyed on the little ones, but adults were not safe, either.

Now the war was his main concern and the dossier that had just arrived from the defense staff convinced him that he must act quickly. American intelligence knew that the Japanese were successfully developing biological weapons. In Manchuria, Unit 731 of the Japanese Army experimented with typhus, plague and cholera. His victims numbered in the hundreds of thousands.

It was essential to have vaccines and medicines that could neutralize a Japanese biological attack. And the US military got down to work and not only to defend itself from attacks on its human population but also to protect animals.

The island of Grosse is a small point on the map in the enormity of Canada. Located on the Saint Lawrence River, this island was the entry and quarantine point for the thousands of Irish emigrants who arrived on the coast of the country fleeing the great famine of 1845-49 due to the poor potato harvest. Many died there of typhus and cholera. It is the largest cemetery due to the great famine outside of Irish territory. It closed its doors in 1932, but reopened them ten years later to, this time, deal with rinderpest.

The Americans knew that if the virus reached their territory, the cattle lacked defenses completely, so it was imperative to immunize them with a vaccine, but to do so, the responsible virus had to be brought to American soil, with the risks that this entailed. The solution? Focus all the investigations on an isolated space such as the Island of Grosse.

The US Army was successful, in 19 months they had a new vaccine ready.

We have already seen how the Japanese knew about the disease and had not stopped making progress on its control: the veterinarian Junji Nakamura managed to attenuate the virus after repeated passage through a non-target intermediate species: the rabbit. Protecting cattle in Japanese territory was critical to the war effort. The American soldier was the best fed of the war, not so the Japanese. Protecting the herds was extremely important. The use of lapinized vaccine (passed more than 100 times per rabbit) was widespread in Asia. The reproduction of the plague virus had no secrets for the Japanese.

On his part, Hitler ruled out biological warfare altogether from the start, and although his lieutenant Himmler toyed with the idea, there were no real efforts to make it happen. This was not the case with the Empire of the Rising Sun.

The Japanese accelerated with their tests and the Americans, on the Island of Grosse, tried to beat them with an effective vaccine, and above all, easy to produce and administer. Work began with the chloroform-inactivated vaccine, but when injected into the calves, they produced only about 350 doses per animal. In 1943, to produce 100,000 doses, 270 bovids were needed. Virologist Richard Shope, in charge of the Canadian facility, estimated that to protect the North American herd, which then numbered about 60 million animals, it would take 170,000 calves and about 60 years of work at the current rate. Obviously, other solutions had to be found. The vaccine could stop small outbreaks, but not protect all livestock.

Shope decided to try a different route: grow the virus in bird eggs. Previous experiences with the flu virus had been successful, so that route was explored. He used the Kabete O strain. The process required passing the virus through a suspension of bovine spleen and then passing it through the chorioallantoic membrane of the egg for 8-12 times. From there it went to the yolk. At that point, the virus replicated with enormous speed invading the embryo and all the fluids that surround it within 24 hours.

This avianized vaccine conferred complete protection within 10 days after administration. And 3-4 doses were obtained per egg. In addition, frozen and vacuum packed, it retained its properties for 15 months. With this vaccine, in 1944, the US was prepared to neutralize a Rinderpest attack by the Japanese.

And the threat was absolutely real. At the forefront of the Japanese effort to infect American cows was the Japanese veterinarian Noboru Kuba. The plan consisted of adding viral preparations to hot air balloons that were built to bomb North American soil (some did hit and one caused the death of 6 people, the only casualties in the American continent from this war). Kuba prepared a mash of infected organs, dried it and obtained 50 grams of highly contagious powder. He did a test with a rocket that after exploding in midair, spread infectious dust around. 10 cows had been placed in the vicinity. The experiment was successful as all 10 cows developed symptoms and died of Rinderpest. The project arrived at Unit 731 (known after the war for its many atrocious experiments, mutilations, tests with the bubonic plague, etc.) with the idea of ​​producing 20 tons of infective powder. The idea reached General Tojo who, although retired, still had an important influence on military decisions. Tojo was convinced that if rinderpest plan succeeded, the Americans would wipe out the rice crop, driving hunger to the heart of the Japanese empire. The plan was aborted.

After the end of the war, the nations collaborated again to end the plague as it continued to rage. Thus, the Chinese herd lost 200,000-300,000 heads each year due to the infection, which condemned many farmers – children included – to pull the plows to get some grain from the land. Starting in 1947, millions of egg vaccine doses arrived from Canada. A network of local laboratories was established to produce the vaccine on site. Unfortunately, it was impossible to multiply the virus in eggs, the goat vaccine produced too severe symptoms in Asian cattle so, finally, the lapinized vaccine was chosen. Each rabbit provided between 300-600 doses, was easy to transport and to replicate. The lagomorph was injected and 3-6 days later it could be sacrificed to procure more vaccines. The program was an absolute success and the last Rinderpest case was declared in China in 1955.

At the international level, nations joined forces (with notable exceptions) to fight hunger. Thus in 1945 the FAO was created, an agency dependent on the UN created for this purpose. FAO took responsibility (in collaboration with the OIE) to help the poorest countries. Provide resources, but above all technical collaboration to eliminate rinderpest. Their performance was key to addressing joint prevention programs, providing vaccines, developing new versions of them, and validating the results once the campaigns had been implemented.

FAO and OIE worked together to control cattle plague

Thailand had carried out many vaccination campaigns but was repeatedly re-infected due to cattle smuggling from neighboring Cambodia. These situations underscored the need for an international effort. With assistance from FAO, Thai technicians developed a lapin vaccine that was adapted to pigs. Much more abundant than rabbits in the region and with a higher yield since up to 800 doses were obtained from each animal.

In 1957, the greatest success, according to the then FAO Secretary-General, was the practical eradication of the disease in Asia and its control, although much remained to be done in Africa.

The 1960s gave another great boost to the fight against the disease. British veterinarian Walter Plouwright was able to reproduce the virus in cow kidney cell cultures. This finding made it possible to dispense with live animals or eggs to keep the virus alive in a laboratory. The new TCRV (Tissue Culture Rinderpest Vaccine) vaccine was safe for all species of livestock, of all ages, conferred lifelong protection, and was cheap and easy to produce.

The only downside is that it needed to be refrigerated. This point was not minor, since reaching remote areas, in Africa, often zones of armed conflict, was not easy. But as this vaccine did not cause the disease or casualties, the farmers allowed the vaccination of their animals without reluctance.

Here is a short video that explains his findings in detail:

The immunization and control of this virus had two factors that facilitated its success. It was fortunate that the characteristics of the virus helped control it, namely:

– The virus has 3 lineages: Asian and African I and II. Immunity against one viral strain conferred protection against all the others, allowing the same vaccine to be used in different areas of the world.

– The reproductive rate (R0) of the virus (the number of animals that an animal carrying the virus can infect) is relatively low. It ranges from 1.5 (lineage II) to 4.6 in Sudan (lineage I). To determine the minimum herd immunity, it is calculated with this formula 1-(1 / R0), which gives a herd immunity requirement ranging from 33 to 78%. In fact, the disease was eradicated from the Somalian region with herd immunity never exceeding 50%.

To give a different example, measles virus has an R0 of 18, therefore it requires a very high immunization rate, over 95% of the population to be effective.

Starting in 1987, FAO established a surveillance program in which, after two years of no cases, the countries stopped vaccinating. It was the only way to verify that the virus was not active since the serology did not distinguish the animals that had antibodies due to the vaccine or to natural infection. If there were no clinical cases in two years after the vaccine was discontinued, FAO determined that the country was free of rinderpest.

Also, towards the end of the 80s another twist came to corner the plague: the veterinarian Jeffrey C. Mariner, together with scientists from the Plum Island research center in NY, after passing the virus through Vero cells (from African green monkey kidney ), got a thermostable vaccine, that is, it did not need refrigeration for 30 days. The TRV or ThermoVax.

The shepherds, ranchers, nomads, veterinarians, authorities, all absolutely all collaborated to vaccinate the animals. New diagnoses also allowed a simple swab applied to one eye to determine in 10 minutes whether or not an animal had antibodies.

Like dominoes, countries were receiving plague-free status: India in 2004, Pakistan in 2007, Ethiopia in 2008, Somalia in 2010. So, it was on May 25, 2011, when the OIE declared all countries free and rinderpest was declared the second disease ever eradicated from planet Earth after smallpox in 1980. A month later the FAO would ratify the OIE declaration.

The efforts to achieve this eradication had an approximate cost of $ 610 million. The benefit is incalculable: millions of people who can escape hunger, avoid suffering and death of millions of animals, the protection of wildlife from a threat that caused countless deaths, in addition to the many learnings obtained to mitigate the impact of other animals and human diseases as well.

Both FAO and OIE have passed resolutions for member countries to destroy their stocks of plague virus that are still stored in various laboratories. 24 countries still have viable virus. The risks are enormous, in case of escape millions of cattle would die, the wild fauna would be in danger, the cost of eradication would be exponential, the paralysis of the cattle trade would slow down livestock development, there would be a certain risk of lack of food, millions of small producers would see their existence and viability compromised.

Furthermore, there is no objective need to maintain virus samples. If a new epidemic were to appear today, it would be possible to gather the genetic information of the virus that is available at GenBank a genetic database that contains the complete sequences of the Nakamura III and Kabete O strains in case it becomes necessary to develop vaccines again.

Today we can celebrate an event like few others in history: the elimination of a virus that caused unimaginable suffering. Thanks to science, today it is part of the past.

A few scientists, with very limited resources, defeated rinderpest. It is only fair that their feat is known and recognized as it deserves.


REVEALED: Zombie outbreak IS possible - and only needs evolution of ONE parasite to happen

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It is one of the greatest fears of humanity, inspired by a bulk of Hollywood movies, and scientists do believe that a zombie outbreak could happen. While it would be impossible to believe that the dead would rise and feed on the living, experts do think that a parasite could affect the brain or a virus could evolve. A parasite called toxoplasmosa gondii is known to infect the brains of rodents.

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A study from the University of California revealed that the parasite is more powerful than previously thought.

Wendy Ingham, who was involved in the study, says that the team tested the parasite on mice which were ultimately unfazed by the presence of a predator once infected.

She warned that toxoplasma is dangerous: &ldquoThe idea that this parasite knows more about our brains than we do, and has the ability to exert desired change in complicated rodent behaviour, is absolutely fascinating.

Rabies has a zombification affect on animals (Image: GETTY)

A zombie outbreak IS possible (Image: GETTY)

&ldquoToxoplasma has done a phenomenal job of figuring out mammalian brains in order to enhance its transmission through a complicated life cycle.&rdquo

Other experts however believe that viruses are what will ultimately turn the human race into zombies.

Dr. Ben Neuman, a professor of virology at the University of Reading, believes that a virus such as rabies could evolve and conquer humanity.

He told Yahoo: &ldquoThere are parasites out there that get close to making actual walking around zombies.


A Cure for Rabies

In September 2004, animal-loving Wisconsin teenager Jeanna Giese picked up a bat trapped inside her church and took it outside. As she tried to set it free, the bat sank its teeth into her left index finger for an instant before she shook it loose.

Back at home, her mother rinsed the tiny wound with hydrogen peroxide and thought no more about it. A month later, the girl, a star student and athlete, developed fatigue, double vision from bilateral sixth nerve palsies, and paresthesias in her left arm. She deteriorated rapidly over the next few days, with high fever, ataxia, confusion, tremor, drooling, and spasm with swallowing, and was intubated for airway protection. Rabies antibody was found in her spinal fluid and serum.

The Fond du Lac girl’s doctors at Children’s Hospital of Wisconsin (Milwaukee) offered the family a dismal choice. She could receive hospice care for the gruesome and invariably fatal consequences of rabies in unvaccinated patients. Or, the doctors could embark on experimental treatment, with no guarantee she would have any meaningful neurological function or quality of life should she survive.

Parents Chose Treatment

On the basis of data indicating rabies patients are capable of clearing the virus, but die largely of secondary complications (e.g., autonomic dysfunction and excitatory neurotoxicity), the team administered massive doses of ketamine, midazolam, and phenobarbital, the antivirals ribavirin and amantadine, and supplementation with coenzyme Q to counter the possible mitochondrial toxicity of ribavirin. Ketamine blocks the neuroexcitatory NMDA receptor, possibly a receptor for rabies virus.

After a stormy, four-week intensive-care course characterized by autonomic instability and other complications, Giese was extubated and went home on New Year’s Day 2005. She made a remarkable recovery, eventually returning to school full time— although she was unable to participate in athletics. At 17, she has been accepted to college to study biology starting this fall.1-3

While the Wisconsin protocol has achieved the previously impossible, it is not yet a surefire cure for rabies. Two U.S. children treated last year with the Wisconsin protocol and meticulous supportive care died—one with cerebral edema, the other with cerebral and cerebellar herniation.4 Additional clinical experience and further tinkering with the protocol are likely required to optimize outcomes.

What To Know

While rabies is rare is the U.S., it retains a disproportionate importance because of its historic 100% fatality rate. Hospitalists should know this about rabies:

Suspect rabies in all patients with undiagnosed neurological disease. Making the diagnosis of rabies as early as possible is more critical than ever, now that a potential treatment exists. Unfortunately, in the United States rabies is rarely considered when patients first present for medical attention.

During the prodromal phase of rabies, which lasts about four days, patients have non-specific symptoms of fever, malaise, and nausea. This is quickly followed by paresthesias at the bite or wound site, personality change and hallucinations, and the classic manifestations of “furious rabies”: agitation, delirium, hydrophobia, aerophobia, aggression, and spasms affecting swallowing and respiration.

In up to 20% of patients, the disease may present in atypical form as “dumb rabies,” an ascending paralysis that may mimic Guillain-Barré syndrome. Tests for rabies include polymerase chain reaction of cerebrospinal fluid or saliva, antibody testing of serum and CSF, and direct fluorescent antibody of biopsy from the nape of the neck, where the virus congregates in hair follicles.

Ask all patients about bat and animal exposure when rabies is in the differential. Worldwide, there are 55,000 cases of human rabies a year. The vast majority of these occur in developing countries as a result of dog bites. In the United States, there is only a handful of human cases of rabies each year, almost always associated with bat exposure. It is not necessary to get a bat bite or scratch to be at risk for rabies. Some U.S. patients seem to have contracted rabies after exposure to bat saliva or vapors, sometimes having been bitten while asleep. Any patient who wakes up in a room or cabin and finds a bat should be considered at risk for rabies.

Other animals commonly infected with rabies in the U.S. include raccoons, skunks, and foxes. Unvaccinated dogs and cats also are at risk of rabies.

Consider prevention the best treatment. Wash bite wounds with 20% soap and irrigate with povidone-iodine to reduce the risk of rabies by up to 90%. If the biting animal is available for observation, the rabies vaccine may be deferred or not administered at all if the animal is well after 10 days. Many state laboratories will also perform rabies testing on euthanized animals. If the biting animal is unavailable for observation, promptly give the rabies vaccine and immune globulin. Current rabies vaccines are safe and highly effective in preventing infection after exposure, provided they are given in a timely fashion. Vaccine and immune globulin have no role in treatment once rabies symptoms have developed. TH

Dr. Ross is an associate physician and hospitalist at Brigham and Women’s Hospital, Boston, and a fellow of the Infectious Diseases Society of America. Contact him at [email protected] .


11 Things We’d Really Like to Know

And a few we’d rather not discuss

The scientific obstacles, though more intractable, are relatively rare.

Many pathogens are genetically farther apart than rhinoceroses and bees: A defense against a horn does not protect against a sting, and vice versa.

Most vaccines work by creating antibodies — Y-shaped proteins — that block the disease agent’s own proteins.

While viruses have only handful of target proteins, bacteria have up to 6,000 and parasites even more, noted Dr. Paul A. Offit, director of vaccine education at the Children’s Hospital of Philadelphia.

And even some smallish viruses, including H.I.V., flu and hepatitis C, mutate so rapidly that their surfaces change shape before antibodies can lock onto them.

As a rule, if a disease normally leaves even a few survivors who are completely disease-free and immune for life, a vaccine against that disease is possible. “Natural infection is the mother of all vaccines,” said Dr. Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases.

Smallpox meets the criteria H.I.V., malaria and tuberculosis do not. H.I.V. mutates as fast in one day as flu does in a year it also survives by splicing its DNA into the very immune cells that hunt it.

TB bacteria can survive even when “walled in” by white blood cells.

And malaria, a shape-shifting parasite, never triggers lifetime immunity. People who survive repeated bouts get less sick each time, but that immunity disappears if they move out of the malarial region. If they return, the first mosquito bite may kill them.

Image

Other diseases are complex, with many subtypes. For example, Pneumovax 23, the anti-pneumonia shot given to middle-aged people, negates 23 strains of one bacterium.

Nonetheless, many diseases now rampaging at large are relatively easy targets, according to interviews with half a dozen experts. They could be beaten with vaccines if the world committed more money.

Lengthy testing, though expensive, is crucial. Vaccines can have dangerous hidden flaws. A 2007 H.I.V. vaccine candidate appeared to increase infection risk among some gay men, though it remains unclear why.

Earlier this year, the use of a new dengue vaccine was restricted to people who had earlier dengue infections because it may have triggered worse outcomes in some people who got dengue after receiving the vaccine.

The relatively easy targets, experts said, include M.E.R.S., Nipah, Lassa, respiratory syncytial virus, Lyme disease, West Nile, Zika and the bacteria that cause strep throat and heart disease.

Thus far, the coalition has raised about $630 million, but its ambitious plans — including DNA and RNA platforms that will cut vaccine-making time to weeks instead of months — will require billions of dollars.

Recent advances in a new tuberculosis vaccine and a new use for an old one have encouraged experts.

“If you’d asked me 18 months ago whether a TB vaccine was possible, I’d have said no,” said Dr. Penny Heaton, chief executive officer of the new Bill and Melinda Gates Medical Research Institute. “But I think the field is now very promising.”

A Lyme vaccine was licensed in 1998 but withdrawn four years later in what has been called “a public health fiasco” after rumors, lawsuits and alarmist media reports scared off customers. Now, with Lyme infecting an estimated 300,000 Americans a year, an improved vaccine is in the works.

Dr. Peter J. Hotez, director of the Texas Children’s Hospital Center for Vaccine Development, has vaccines against hookworm and schistosomiasis, a waterborne liver fluke, in clinical trials and is working on eight others.

Some candidate vaccines rely on startling mechanisms for defeating the dizzyingly complex parasites — including injecting humans with a gene that produces an antibody that destroys a worm’s gut when it sucks blood.

But, like all the other projects in the works, that one needs more money — and not just from the usual suspects (the United States, Britain and the Gates Foundation).

“In this multi-trillion-dollar economy,” Dr. Hotez said, “it’s a little discouraging that we can’t raise the funding.”