Mumps in children is usually so mild that even WHO does not scare anyone with it. In adults, however, they say that mumps can cause severe complications. Hence it is important to vaccinate infants.
CDC Pinkbook Mumps
In pre-vaccination times, 15-27% of mumps cases were asymptomatic. The number of asymptomatic cases today is unknown, as it is unclear how the vaccine modifies clinical symptoms. Orchitis (testicular inflammation) is the most common complication of mumps, but it is only possible in post-pubertal males. Orchitis is primarily unilateral. Infertility caused by mumps orchitis is quite rare, even in cases of bilateral orchitis.
Prior to introduction of the vaccine, cases of mumps were not recorded.
Monovalent mumps vaccine is virtually non-existent today, except for Japan, where MMR is still banned, mumps vaccine is not sponsored by the state, and very few people get vaccinated against it.
Vaccine against mumps.
Mumps is a relatively mild childhood disease, but it is inconvenient, since children have to miss school. Severe mumps complications are rare.
Significantly fewer antibodies are formed after vaccination than after the disease.
Despite the fact that recently released mumps vaccine looks promising, there is no need for mass vaccination.
Prevention of mumps.
13 years later, BMJ wonders again whether the UK needs yet another vaccine for infants.
Mumps is not subject to registration, thus the number of cases is unknown, especially since 40% of mumps cases are asymptomatic. Perhaps a combination vaccine with measles is justifiable. This vaccine could be given to children when they start school, for those who have not yet had mumps or measles.
Would the 50% of parents, who agree to the measles vaccine today, agree to another vaccine in addition to it? Only if the unwarranted but widespread fear of infertility from orchitis will outweigh the British distrust of new vaccines. Otherwise, this vaccine will not be in demand.
However, even low vaccination coverage can lead to an increase in the number of adults susceptible to mumps. It is already happening in the US.
For someone who has not had mumps, the vaccine could be a blessing, but for society as a whole, it would be quite the opposite, as the current situation when 95% of adults are immune to mumps would change. This disease may be unpleasant, but it is rarely dangerous. An attempt to prevent it on a massive scale could lead to an increase in disease incidence in adults, with all the risks associated with it.
A retrospective survey of the complications of mumps.
J R Coll Gen Pract
Here is the analysis of 2,482 cases of mumps hospitalization in 1958-1969 in 16 hospitals in England. They constitute the majority of mumps cases that required hospitalization in the country. Half of the patients were 15 years old or older. Complications were recorded in 42% of all cases. Three patients died, but two of them had another serious underlying illness and mumps might not have had anything to do with the death, and the third patient was most probably misdiagnosed and did not even have mumps. The only complication, which may have been permanent, was deafness in five patients (four of them were adults).
Meningitis in mumps happens so often that some people believe it should not even be considered as a complication, but rather an integral part of the disease. In any case, there is a consensus that mumps meningitis is not dangerous and rarely has any consequences. It is confirmed by this study.
What is usually most feared is orchitis. There is a general fear of infertility from orchitis, but its probability is overestimated. Even though it is impossible to exclude, a small retrospective study did not detect infertility as a consequence of orchitis.
The authors conclude that there is no need for mass vaccination against mumps. It might make sense to vaccinate post-pubertal teenagers on admission to boarding school or the army. Even then, however, it should be remembered that 90% of the boys have already had mumps by the age of 14, which is why they should be checked for antibodies first, and only those who do not have the antibodies should be vaccinated.
Reports of sensorineural deafness after measles, mumps, and rubella immunization.
Arch Dis Child
Here is the description of 9 cases of deafness after the MMR vaccine within four years of vaccination. The authors conclude that in 3 cases deafness was unrelated to the vaccine (but they do not provide an explanation for this conclusion), and in 6 other cases it may or may not have been related to the vaccine.
Since unilateral deafness is hard to diagnose in children, and they get vaccinated at the age of 12 months, there may have been other cases that were missed.
The authors suggest checking children’s hearing upon admission to school and comparing it to historical data, in order to understand whether the MMR vaccine affects hearing.
Another 44 cases are described here.
A few more cases of deafness after the MMR vaccine: , , , , , , , , , .
Here is the report of 119 cases of meningoencephalitis caused by mumps in San Francisco in 12 years (1943-1955). Most cases are mild, with no complications, no neurological consequences, last less than 5 days, and rarely require hospitalization. Death due to mumps meningoencephalitis is a very rare phenomenon, and in the entire medical literature only 3 such cases have been described (including one out of these 119).
Mumps in the workplace. Further evidence of the changing epidemiology of a childhood vaccine-preventable disease.
20 years after the invention of the vaccine and 10 years after it became widely used, the first mumps outbreak (118 cases) occurred in the workplace (Chicago Futures Exchange). Total costs associated with the outbreak amounted to $120,738, whereas the vaccine costs only $4.47.
The authors report that historically, vaccine prevention of mumps did not get as much attention as the other diseases, because it is a mild one. However, $1,500 per case of mumps is too expensive, when the vaccine only costs $4.47 in public and $8.80 in private sectors. Research shows that every dollar invested in the mumps vaccine, saves $7-$14.
In addition, mumps in adults often leads to complications. 10-38% of post-pubertal men get orchitis. Also, mumps patients often develop meningitis (0.6% of cases among those aged 20 years or more). Getting mumps during the first trimester of pregnancy increases the risk of miscarriage.
In pre-vaccination times, mumps outbreaks were observed mainly in prisons, orphanages and army barracks.
The effectiveness of the mumps component of the MMR vaccine: a case control study.
Mumps outbreak in London. 51% of the patients had been vaccinated. The effectiveness of one dose of the vaccine is 64%. The effectiveness of two doses – 88%. This effectiveness is much lower than is stated in clinical trials, since immunogenicity (i.e. the amount of antibodies) is not an accurate biological marker of the vaccine effectiveness. Moreover, the vaccines might have been improperly stored, which could have caused them to lose their effectiveness.
The authors also analyze other studies of the mumps vaccine effectiveness. In the 60s, the effectiveness was 97%, in the 70s it was 73-79%, in the 80s – 70-91% and in the 90s – 46-78% (87% for the Urabe strain).
Vaccine-related mumps infections in Thailand and the identification of a novel mutation in the mumps fusion protein.
Two weeks after the MMR vaccination of nursing students in Thailand, an outbreak of mumps occurred. The vaccine strain of the virus (Leningrad-Zagreb) was found in those infected. This strain has repeatedly caused mumps outbreaks before.
Waning immunity against mumps in vaccinated young adults, France 2013.
In 2013, 15 mumps outbreaks were registered in France. 72% of the cases had been vaccinated twice. The effectiveness of the vaccine was 49% for one dose and 55% for two doses.
Among those who had been vaccinated once, the risk of getting mumps increased by 7% for every year that had passed since the vaccination.
Among those who had been vaccinated twice, the risk of getting mumps increased by 10% for every year that had passed after the second dose.
Orchitis was observed in five men. One of them was unvaccinated, two had been vaccinated with one dose, and another two had been vaccinated twice.
Mumps is a mild disease, which passes on its own, but sometimes it can cause severe complications, such as orchitis, meningitis, pancreatitis or encephalitis, especially in adults. Complications from mumps are observed more often in adults and they are more severe than in children, especially among the unvaccinated.
In other countries, mumps outbreaks are also observed among the vaccinated. The reason for this is the decreasing effectiveness of the vaccine and the lack of natural boosters. Other reasons for the outbreaks could be the initial overestimation of the vaccine effectiveness, insufficient vaccination coverage, or existence of a strain that is not covered by the vaccine.
Outbreaks occurring among the vaccinated and the decreasing effectiveness, both lead to thoughts about a third dose of the vaccine. This kind of an experiment was conducted in the US during the outbreaks in 2009 and 2010. Both times the outbreak subsided a few weeks after the administration of the vaccine. However, the outbreaks always subside at some point, so it was unclear whether it had anything to do with the vaccination. Nonetheless, this and other experiments hint that a third dose of the vaccine might not be a bad idea. Moreover, during the vaccination campaigns in the US, the third dose had few side effects.
They wanted to introduce a third dose of MMR into the national immunization schedule in Netherlands, but changed their mind, since mumps rarely causes complications, and the vaccination coverage among adults is unlikely to be satisfactory.
Mumps outbreaks among the vaccinated, along with this study, led the Ministry of Health of France to recommend a third dose of MMR at times of outbreaks. Even though it is unknown whether the vaccine is effective for those already infected with the virus, it is quite possible that the vaccine will cause a decrease in the contagious period of the vaccinated patients.
The Dutch study determined that two thirds of cases during outbreaks are asymptomatic. The role of asymptomatic patients in the transmission of the disease remains unknown.
Future observations in France, and possibly other countries that would adopt the same recommendation, will help determine whether the third dose of MMR is effective during outbreaks.
Mumps outbreak in Israel's highly vaccinated society: are two doses enough?
A mumps outbreak in Israel (over 5,000 cases). 78% had been fully vaccinated. Mostly teenagers and adults got sick. In other countries (Austria, USA, Netherlands, Great Britain) mumps outbreaks were also observed among teenagers and college students, whereas in countries where there is no vaccination against mumps, children aged 5-9 years got sick.
Despite the high vaccination coverage (90-97%), mumps antibodies were found in only 68% of the population.
The authors report that the recent mumps outbreaks have been caused by the genotype G virus, whereas the vaccine contains genotype A. However, they do not believe that it is related to the outbreaks and suggest introducing a third dose of the vaccine.
Mumps outbreak in a highly vaccinated school population. Evidence for a large-scale vaccination failure.
Arch Pediatr Adolesc Med
Mumps outbreak in a school where all but one of the students had been vaccinated. 54 cases in total.
There are many similar studies on mumps outbreaks among fully vaccinated. Here are a few more:
, , , , , , , , , , , , , .
The vaccine against mumps is so ineffective, and the outbreaks among fully vaccinated are so common, that there is a special article on Wikipedia, listing all the mumps outbreaks in the 21st century.
Transmission of mumps from mumps-vaccinated individuals to close contacts.
Mumps infection but not childhood vaccination induces persistent polyfunctional CD8+ T-cell memory.
J Allergy Clin Immunol
Upon getting infected with mumps, polyfunctional memory T-cells are produced, but they are not produced upon vaccination. Perhaps this could explain why the vaccine only gives temporary immunity.
Serological survey of mumps antibodies in adults in the Czech Republic and the need for changes to the vaccination strategy.
Hum Vaccin Immunother
Among the 18-29 years age group in Czech Republic, only 19% of those vaccinated against mumps had antibodies. Among the unvaccinated of the same age group, 48% had antibodies.
Among those unvaccinated aged 40 years and over, 63% has mumps immunity.
Despite the vaccination coverage of 98%, mumps outbreaks in Czech Republic did not stop, but rather the incidence of mumps shifted to the older age group.
In 2010, two virologists, who had previously worked for Merck, sued the company. They claimed that Merck manipulated the results of the mumps vaccine clinical trial, which allowed the company to remain the exclusive MMR manufacturer in the United States.
The lawsuit states that Merck organized a fictitious vaccine-testing program in the late 90s. The company obliged the scientists to participate in the program, promising them all bonuses if the vaccine got certified, and threatening prison if they were to report this fraud to the FDA.
The effectiveness of the mumps vaccine is determined in the following way. A blood sample is taken from children before and after vaccination. After that, a virus is added to the blood, which creates plaques as it infects the cells. Comparing the amount of these plagues in the blood before and after vaccination indicates the effectiveness of the vaccine.
Instead of testing how children’s blood neutralizes the wild virus strain, Merck was testing how it neutralizes the vaccine strain. However, this was still not enough to demonstrate the required 95% effectiveness. Thus, rabbit antibodies were added to the tested children’s blood, bringing the effectiveness level to 100%.
And that is not all of it. Since adding animal antibodies showed pre-vaccine effectiveness of 80% (instead of 10%), the fraud was evident. First, the number of added rabbit antibodies was changed, but it did not give the desired results. So they simply began to falsify the plaque counting, and counted plaques that actually were not in the blood. Falsified data was entered into an Excel file, since changing paper forms took too much time, plus this tactic did not leave any traces of falsification.
Still, the virologists did contact the FDA and the FDA sent an agent for a check. She asked questions for half an hour, received false answers, did not ask any questions the virologists themselves, did not check the lab, and wrote a one-page report, pointing to some minor issues with the process, but never mentioning neither the rabbit antibodies nor the falsified data.
As a result, Merck has received the MMR and MMRV certification, and is the sole manufacturer of these vaccines in the United States.
After the big mumps outbreaks in 2006 and 2009, the CDC, which planned on eliminating mumps by 2010, shifted the goal date to 2020.
When the court asked Merck to provide evidence of the vaccine effectiveness, they provided data from 50 years ago.
All MMR safety studies described in the section about measles are applicable to mumps as well. Here are some more:
Outbreak of aseptic meningitis associated with mass vaccination with a urabe-containing measles-mumps-rubella vaccine: implications for immunization programs.
Am J Epidemiol
After the mass MMR vaccination campaign in Brazil with the Japanese strain of mumps (Urabe), an outbreak of aseptic meningitis began. The risk of disease increased by 14-30 times.
The fact that Urabe strain is associated with aseptic meningitis was already known, but Brazilian authorities decided to use this strain anyway, as it is cheaper and more effective than the Jeryl Lynn strain (which is used in the US), and because they thought the risk of meningitis was quite low.
In France, vaccination with the same strain did not cause a meningitis outbreak. The authors attribute this phenomenon to the fact that the outbreaks in Brazil were observed mainly in the large cities, where people live close to hospitals. Moreover, a large number of children had been vaccinated in a very short time. These factors made it possible to identify the outbreak.
The authors worry that such side effects could lead to more people refusing vaccination. They say that people’s belief in the benefits of vaccination is no longer strong enough on its own, and that more and more people refuse vaccination, and that it would not hurt to also record side effects of the vaccination.
Urabe strain had been used in Great Britain since 1988, and stopped being used in 1992, only after the manufacturers declared that they are stopping production. However, according to the published documents, authorities knew about the dangers of this strain in 1987 already.
Outbreak of aseptic meningitis and mumps after mass vaccination with MMR vaccine using the Leningrad-Zagreb mumps strain.
The following year, learning from their mistakes, the Brazilian authorities bought MMR with another strain of mumps (Leningrad-Zagreb) and vaccinated 845 thousand children with it. Another outbreak of aseptic meningitis started, and this time the risk of disease was 74 times higher. Sure, it was known that this strain also increases the risk of meningitis, but since the vaccination campaign in the Bahamas did not cause a meningitis outbreak, they decided to see how it would turn out in Brazil. Moreover, a mumps outbreak also began. One out of every 300 doses of the vaccine resulted in mumps.
The authors are wondering whether all the vaccination campaign funding should be used on vaccines, or maybe some of it should be allocated to registering side effects. They write that this issue is quite controversial in the medical literature. Supporters of prioritizing the vaccine believe that benefits of vaccination campaigns are indisputable, and that there is no need to spend money on such nonsense. Proponents of side effects monitoring believe that lack of information scares people and leads to distrust of the vaccines.
Leningrad-Zagreb strain was developed in Serbia on the basis of Leningrad-3 strain, which also caused meningitis.
A population-based case-control study on viral infections and vaccinations and subsequent multiple sclerosis risk.
Eur J Epidemiol
In those who had been vaccinated with MMR before the age of ten, the risk of multiple sclerosis was 5 times higher.
Henoch-Schönlein purpura and drug and vaccine use in childhood: a case-control study.
Ital J Pediatr
In those vaccinated with MMR, the risk of hemorrhagic vasculitis was 3.4 times higher. In children, this disease usually goes away on its own, but in 1% of cases it can lead to kidney failure.
Mumps vaccine associated orchitis: Evidence supporting a potential immune-mediated mechanism.
Deep sequencing reveals persistence of cell-associated mumps vaccine virus in chronic encephalitis.
A 14 months old boy was given an MMR vaccine, and 4 months later he was diagnosed with a severe combined immunodeficiency. He then successfully underwent a bone marrow transplant, but developed chronic encephalitis, and died at the age of 5. A brain biopsy showed that he had the vaccine strain of the mumps virus in his brain. This was the first case of panencephalitis caused by the mumps virus.
Several studies, according to which, childhood mumps is associated with a reduced risk of cancer, neurological and cardiovascular diseases, were sited in the previous section, among other things. Here I will focus more on the ovarian cancer.
Epidemiologic study of malignancies of the ovaries.
Unlike other types of cancer, whose risk increases with age, the risk of ovarian cancer increases till the age of 70, and then decreases sharply. The risk of ovarian cancer in Japan is much lower than in England and the US, where this type of cancer is becoming more common.
The authors analyzed the relationship between ovarian cancer and 50 different factors, and found that the only statistically significant factor associated with ovarian cancer was not having had mumps in childhood (p=0.007). In fact, not having had rubella as a child was also associated with ovarian cancer, but in this case p-value was equal to 0.02. Back then, scientists had slightly more self-respect, and p>0.01 was not considered statistically significant.
It was also found that the risk of ovarian cancer in unmarried women was significantly higher.
Possible role of mumps in the etiology of ovarian cancer.
Clinical mumps in childhood is associated with a reduced risk of ovarian cancer. Moreover, it turned out that patients with ovarian cancer had less mumps antibodies.
The authors believe that what influences the risk of ovarian cancer is not the actual mumps infection, but rather the subclinical course of the disease. In case of the subclinical disease (without symptoms, like after vaccination) less antibodies are produced, which is what subsequently protects against cancer.
Mumps and ovarian cancer: modern interpretation of an historic association.
Cancer Causes Control
In addition to these two, seven more studies have been published on the association of mumps with the reduced risk of ovarian cancer. Nonetheless, the biological mechanism of this phenomenon has not been studied, and with the beginning of vaccination the connection between mumps and ovarian cancer became irrelevant, and was forgotten.
All but two of the studies found the protective effect of mumps against ovarian cancer. One of the two studies, which did not find the connection, did not even find the connection between pregnancy and ovarian cancer. The second study (the last one out of nine), was conducted in 2008, and already includes many more vaccinated people than the previous ones.
MUC1 is a membrane protein, which is associated with cancerous tumors. The authors found that women who have had mumps had much more antibodies to this protein than those who did not have mumps. This biological mechanism is what explains the protective function of mumps.
Mumps vaccine creates antibodies against the virus, but does not create antibodies against MUC1. To create these antibodies one needs to actually having mumps. Thus, it is possible to conclude that since symptomatic cases of mumps after the beginning of vaccinations are observed much less frequently, it will lead to an increase in the incidence of ovarian cancer. Indeed, the incidence of ovarian cancer among white women has already increased.
The authors also conducted a meta-analysis of the eight studies, and concluded that having had mumps decreases the risk of cancer by 19%.
Oncolytic activities of approved mumps and measles vaccines for the therapy of ovarian cancer.
Cancer Gene Ther
Ovarian cancer is the fourth leading cause of death among American women. 25 thousand women get diagnosed each year, and 16 thousand of them die. The authors analyzed three viruses: a recombinant measles virus and vaccine strains of mumps and measles, as treatment for ovarian cancer in vitro on mice. All three viruses successfully killed cancer cells. Despite the excellent results, they did not start using the virus as part of the conventional cancer therapy. Perhaps because this strain can cause complications of the nervous system.
The authors notice that since most people in Western countries are vaccinated against measles and mumps, the immune system can interfere with this type of therapy.
Treatment of human cancer with mumps virus.
90 patients in terminal stage of cancer tried the mumps virus treatment (wild or almost wild strain). The virus was given orally, rectally, intravenously, by inhalation, by local injection, or simply by applying externally to the tumor. Since the researchers did not have enough virus, patients received only small amounts.
37 patients demonstrated very good results (the tumor disappeared completely or shrank by more than 50%), 42 patients had good results (the tumor shrank or stopped growing). Just few days later the patients had less pain and improved appetite, and within two weeks the tumor disappeared completely in many patients. Side effects were minimal. 19 patients were cured completely.
Studies on the use of mumps for the treatment of human cancer.
Two hundred cancer patients got intravenous injections of mumps virus (Urabe strain). The only side effect was a slight fever in half of the patients.
In 26 patients regression of the tumor was observed. In majority of the patients the pain was alleviated. In 30 out of 35 patients, the bleeding decreased or stopped. In 30 out of 41 patients, ascites and swelling decreased or disappeared.
Attenuated mumps virus therapy of carcinoma of the maxillary sinus.
Int J Oral Surg
Two patients with maxillary sinus carcinoma got injected with the mumps virus (Urabe strain). Their pain was immediately alleviated and the tumor regressed. However, later they still died of exhaustion.
Recombinant mumps virus as a cancer therapeutic agent.
Mol Ther Oncolytics
All three of the previous studies were conducted in Japan, and the results were of no interest to anyone outside the country. Then, in 2016, the notorious Mayo Clinic decided to take samples of this virus from Japan and test them in vitro and on mice. It turned out that indeed, the virus has an anti-cancer effect.
The use of fetal bovine serum: ethical or scientific problem?
Altern Lab Anim
One of the MMR components (and some other vaccines) is fetal bovine serum. Cells, in which the virus is grown, need to multiply. To do so, they need a nutrient medium with hormones, growth factors, proteins, amino acids, vitamins, etc. Fetal bovine serum is usually used as this medium. Since the serum should preferably be sterile, the blood of calves' fetuses is used instead of the cow’s blood.
A pregnant cow is killed and the uterus is removed. Then the fetus is removed from the uterus, the umbilical cord is cut and disinfected. After that the heart is punctured with a needle and the blood is pumped out. Sometimes a pump is used for this, sometimes a massage. After the blood coagulates, platelets and coagulation factors are separated from it by centrifugation. Fetal bovine serum is what remains as a result.
Apart form the necessary components, the serum can also contain viruses, bacteria, yeast, fungi, mycoplasmas, endotoxins, and possibly prions. Many components of bovine serum have not yet been identified, and the function of many of the identified ones is unknown.
150 ml of serum can be collected from a three months old fetus, 350 ml from a six month old, and 550 ml from a nine month old fetus. (Cows’ pregnancy lasts 9 months). The global market for bovine serum is 500,000 liters every year, which requires approximately 2 million pregnant cows. (Currently, the serum market is already 700,000 liters).
The authors then go on to analyze the literature on the subject of whether the fetus suffers when its heart is punctured and its blood is pumped out.
Since the fetus experiences anoxia (an acute oxygen deficiency) when separated from the placenta, perhaps it could prevent the pain signals from reaching the brain, and the fetus might not suffer. However, it turns out that, unlike adult rabbits, who die of anoxia within 1.5 minutes, prematurely born rabbits can live without oxygen for 44 minutes. This happens because fetuses and newborns compensate for oxygen deficiency with anaerobic metabolism. Moreover, fetal brain consumes much less oxygen than adult brain. Other species of animals show similar results, but calves have never been examined specifically.
Science has only recently raised the issue of whether a mammal’s fetus or newborn feels pain. Just ten years ago, infants were believed to be less sensitive to pain than adults, which is why surgeries on premature and full-term infants were performed without anesthesia. Today, it is believed that human fetus can feel pain as early as 24th week of pregnancy, and can suffer starting from week 11 after conception. Moreover, fetuses and newborns are more sensitive to pain than adults, since they have not yet developed a mechanism for suppressing physiological pain. Therefore, a fetus can even feel pain form a simple touch.
The authors conclude that normal brain activity is observed in fetus when its heart is being punctured, it feels pain and suffers when the blood is pumped out, and maybe even after the procedure, until it dies.
The authors then discuss whether it is possible to anesthetize the fetus, so that it would not feel pain. Some believe that anoxia itself plays a role of anesthetic, but that is not the case. In addition, newborn mammals have poor capacity to metabolize drugs. Also, it is undesirable to have these drugs in the serum. Electrical stunning cannot be used either, since it causes cardiac arrest. The authors believe that, perhaps, a bolt, appropriately stunned into the brain, would induce brain death.
Some manufacturers claim that they kill the fetus before harvesting blood, but that is not true, since the blood clots right after death, and to collect it the fetus must be alive.
The authors conclude that the procedure of harvesting the fetal bovine serum is inhumane.
Benefits and expenses due to animal serum used in cell culture production.
Dev Biol Stand
20-50% of fetal bovine serum is infected with bovine viral diarrhea virus, as well as other viruses.
We are talking only about the viruses known to science, which constitute only a small fraction of all the existing viruses.
Fetal Bovine Serum RNA Interferes with the Cell Culture derived Extracellular RNA.
Fetal bovine serum contains extracellular RNA, which is impossible to separate from the serum. This RNA interacts with human cells RNA, in which vaccine viruses are grown.
Evidence of pestivirus RNA in human virus vaccines.
J Clin Microbiol
The authors examined five types of live vaccines and detected bovine viral diarrhea virus RNA in MMR vaccines of two different manufacturers, as well as in two monovalent vaccines against mumps and rubella, which most likely got there from fetal bovine serum.
In infants, this virus might cause gastroenteritis, and in pregnant women, it might lead to the birth of children with microcephaly.
Viral contamination of bovine foetal serum and cell cultures.
The fact that fetal bovine serum is infected with the bovine viral diarrhea virus was known already in 1977. It is known that this virus passes through placenta and can infect the calf fetus in the uterus. 60% of serum samples in Australia were contaminated with the virus. 8% of the vaccines against Bovine Rhinotracheitis were also contaminated.
The virus was also found in bovine kidney cells, which are used in production of measles vaccine.
Pertussis toxin is required for pertussis vaccine encephalopathy.
Proc Natl Acad Sci U S A
When mice were injected with pertussis toxin, none of them died. Whereas, when they got injected with pertussis toxin together with bovine serum albumin (a fetal bovine serum component), most of them showed lethal encephalopathy.
In vitro inhibition of mumps by retinoids.
Vitamin A inhibits the replication of mumps virus in vitro.
Klenner used vitamin C to treat mumps and its complications.
A bit of history
The benefits of mumps
Fetal bovine serum