TURSDAY June 26, 2008 (foodconsumer.org) -- The Centers for
Disease Control and Prevention on Wednesday June 25 released a report saying
that the onset of rotavirus activity in the ongoing 2007-2008 season seems to
have been delayed and the activity appears to be the least severe than any
previous seasons, an observation that the agency suggests is due to the newly
introduced rotavirus vaccine.
The report published in the agency's publication known as Morbidity
and Mortality Weekly Report (MMWR) says that data from around the United States
indicated that during the ongoing season, rotavirus activity was delayed by
about three months, the latest compared to any previous seasons in the past 15
years since the agency started monitoring the virus.
In this season, rotavirus began to be active at the end of
February, 2008 instead of last November, the usual onset time and the reason
peaked at the end of April, 2008 instead of March, the usual peak time, the CDC
says in a statement.
Rotavirus is the leading cause for severe gastroenteritis
leading to diarrhea and vomiting in infants and young children.
The virus causes 410,000 physician office
visits, 205,000-272,000 emergency department visits and 55,000-70,000 hospitalizations,
but it rarely causes deaths in children younger than 5 in the United States (20
to 60 deaths each year).
The CDC says since the introduction of Merck's rotavirus
vaccine RotaTeq, hospitalizations, emergency department visits, and physician
visits were substantially reduced at selected medical centers conducting
prospective rotavirus surveillance by the government.
The number of lab tests performed for rotavirus from Jan. 1
to May 3, 2008 was reduced by 37 percent compared to the usual. Among the
tests, the positive rate for gastroenteritis was 79 percent lower than usual.
RotaTeq, manufactured by Merck & Co. Inc. was approved
in 2006 and recommended for routine immunization of U.S. infants at 2, 4 and 6
months of age.
The CDC cites trial data in its press release saying the
live oral vaccine is able to prevent 74 percent of all rotavirus cases, about
98 percent of severe cases and about 96 percent of hospitalizations caused by
"The changes appear to be greater than expected based
on the protective effects of the vaccine alone," said Dr. Anne Schuchat,
director of the National Center for Immunization and Respiratory Diseases at
"It is also possible that current levels of vaccination
may be helping to decrease the spread of rotavirus to unvaccinated individuals
in the community. Ongoing monitoring is needed to confirm the impact of
vaccination this year and to monitor the impact of the vaccine on rotavirus
disease and its epidemiology over time."
The new surveillance data did not come from all county
Rather they were reported
weekly from the New Vaccine Surveillance Network, which tracks the virus in
three counties and the tests were performed by the National Respiratory and
Enteric Virus Surveillance System (NREVSS), the Los Angeles Times reports.
There are some limitations to the surveillance data, editors
of MMWR say in their editorial note included in the report.
The following is cited in verbatim from the report.
The findings in this
report are subject to at least five limitations. First, the 2007--08 rotavirus
season is still ongoing, and further information is needed to evaluate
rotavirus activity fully. Second, although most laboratories submit reports to
NREVSS within 2 weeks of testing, delays in reporting might have some effect on
these preliminary data. Third, testing for rotavirus is not part of routine
clinical practice and is conducted at the discretion of the physician and based
on institutional policies. Changes in testing practices might impact these
findings; however, such changes would be unlikely to explain the large decline
in positive test results in 2008, particularly given the consistency of this
decline across participating laboratories. Fourth, because NREVSS is a purely
laboratory-based surveillance system, patient-level information is not
available and NREVSS might receive more than one result for a given patient.
However, any contribution of this to the results likely would be small.
Finally, the counties where NVSN conducts active surveillance might not be
representative of the entire U.S. population; however, the findings from NREVSS
support very similar interpretation.
The rotavirus vaccine is not free of adverse effects. The
Food and Drug Administration published RotaTeq™ Questions and Answers giving the
public some ideas what kinds of side effects the vaccine may cause cited in
verbatim as follows.
The following were
reported more often in infants who received RotaTeq™, when compared to those
who received placebo; diarrhea (24.1% in vaccine recipients vs 21.3% in those
receiving placebo), vomiting (15.2% in vaccine recipients vs 13.6% in those
receiving placebo), ear infection (14.5% in vaccine recipients vs 13.0% in
those receiving placebo), runny nose and sore throat (6.9% in vaccine
recipients vs 5.8% in those receiving placebo), wheezing and coughing (1.1% in
vaccine recipients vs 0.7% in those receiving placebo).
The vaccine is designed to prevent gastroenteritis, which
causes diarrhea and vomiting. It is ironic that those who received the vaccine
seemed to have slightly high incidents of these symptoms compared to those who
Rotavirus is transmitted by the facal-oral route via contact
with contaminated hands, surfaces and objects and possibly by the respiratory
route. The virus is highly contagious. The faces of an infected person can
contain more than 10 trillion infectious virus particles per gram, but only 10
to 100 of them are enough to cause an infection in another person, according to
To prevent an infant from
getting the virus, family members should practice good hygiene and wash their
hands before they walk out of the bathroom.
Disclaimer: What's published on this website should be considered opinions of respective writers only and foodconsumer.org which has no political agenda nor commercial ambition may or may not endorse any opinion of any writer. No accuracy is guaranteed although writers are doing their best to provide accurate information only.
The information on this website should not be construed as medical advice and should not be used to replace professional services provided by qualified or licensed health care workers. The site serves only as a platform for writers and readers to share knowledge, experience, and information from the scientific community, organizations, government agencies and individuals.
Foodconsumer.org encourages readers who have had medical conditions to consult with licensed health care providers - conventional and or alternative medical practitioners.