As reported by the New Haven Register, April 30, 2006.

Spread of Mumps Could Be Stopped with Immunizations

By Abram Katz

Mumps, the childhood virus of "chipmunk cheeks" and days home from school, has surged in the United Kingdom and the midwestern United States and the disease could easily spread east, infectious disease specialists caution.

Traveling through insufficiently vaccinated adults and populations without collective immunity, the paramyxovirus created about 70,000 cases in Great Britain from 2004 to 2006 and about 700 suspected, probable and confirmed cases in the Midwest since late 2005, according to the U.S. Centers for Disease Control and Prevention.

The mumps causes a rash, flu-like symptoms and swollen salivary glands in children. Men may suffer inflamed testis, leading to sterility, and adults can develop encephalitis or meningitis.

Virologists suspect that the virus may have traveled via an infected person from the U.K. to the U.S., since both strains appear the same. Since passenger jets can transport a human vector to any literally any city in a matter of hours, mumps could appear almost anywhere, said Dr. Robert S. Baltimore, a specialist in pediatric infectious diseases at the Yale School of Medicine.

"It's a legitimate concern that the mumps will spread. It's not unreasonable to be concerned about it spreading. One infected person traveling could spread the disease," he said.

Connecticut has among the highest rates of immunization in the country because children entering school must receive a measles-mumps-rubella vaccine, Baltimore said. College students are also required to provide proof that they have received an MMR booster.

The mumps outbreaks emphasize the importance of booster shots, said Dr. John Shanley, director of infectious diseases at the University of Connecticut Health Center.

"This is pointing up the frailty of the vaccine. People don't really appreciate it. It takes 25 years for it to become obvious," Shanley said. "If you don't participate in vaccination, it can come back and bite you."

People who have had a case of mumps remain immune for life.

Baltimore said the Midwest cases are probably a sign that the vaccine was not completely effective.

"A substantial number of mumps patients in the Midwest were vaccinated. But the vaccine is not 100 percent," he said. Others probably did not respond to the vaccine or declined to be vaccinated, Baltimore said.

The United States has had sufficient "herd" immunity against mumps, meaning that a sufficient percentage of people were protected to prevent outbreaks, he said.

The un- and under-vaccinated population tipped the herd immunity. About 80 percent of patients respond to one dose of vaccine. Two doses increases immunity to about 95 percent, he said.

However, mumps is so contagious that 95 percent immunity is necessary to stop the spread of the virus, he said.

Baltimore said Yale and the Yale School of Public Health Emerging Infections program are taking several measures to defend against mumps.

Yale-New Haven Hospital is actively looking for mumps and considering what course of action it would take. Meanwhile, anyone born after 1957 who has not received two MMR vaccines should get an immunization update, he said.

Baltimore said Yale is also interested in why people refuse immunizations and how to develop programs that would help people see the value of vaccines.

Some people contend that vaccines are responsible for a range of ills, including autism. However, no studies support this alleged link.

The university is also investigating whether use of a "weak" vaccine could encourage the rise of resistant viruses, Baltimore said.

The CDC is studying non-vaccination, he said. Children whose parents refuse vaccination are distributed evenly in urban regions, he said. Rather, they are concentrated by country of origin, religion, ethnicity, distrust of the government and other factors.

Thus, the overall rate of vaccination may appear high, but the area may contain pockets of susceptible people. This could lead to outbreaks, Baltimore said.

"I do hear about parents who want to back off from vaccinations," said Dr. David Lobo, infectious diseases specialist at Bridgeport and Milford hospitals.

"I hope herd immunity is not declining," he said.

Mumps is very contagious and spread by respiratory droplets. The virus concentrates in the parotid glands, which are large saliva-producing organs below the ear and next to the lower jaw.

The glands usually remain inflamed for about seven days and then resolve, Lobo said.

Males past puberty who develop mumps have a 15 percent to 20 percent risk of testicular inflammation, or orchitis. Orchitis can result in sterility, he said.

Men and women may also experience encephalitis, or inflammation of the brain. The condition is usually mild but can result in permanent nerve or brain damage.

Mumps can also cause inflammation of the pancreas. Recovery usually takes a week.

Outbreaks of other viruses are more ominous.

West Nile virus, for example, appeared suddenly and spread across the United States. "We still don't know how West Nile virus got into the U.S.," Baltimore said.

"With international travel and commerce, it's likely that diseases are spreading more rapidly than in the past," he said.

Severe Acute Respiratory Syndrome appeared in Asia in 2003, origin unknown. During 2003 the corona virus killed an estimated 774 people. Then it retreated.

"We learned a tremendous amount about it in the first year, including why it spread," Baltimore said. Why SARS has not re-emerged is not known.

Abram Katz can be reached at akatz@nhregister.com or 789-5719.