Epidemiologist Studies Impact of Common but Deadly Virus

An estimated 22 million infants are not fully immunized with routine vaccines every year and more than 1.5 million children younger than five die from diseases such as diphtheria, measles, pertussis, pneumonia, polio, rotavirus, rubella and tetanus that could be prevented by existing vaccines.

As a part of World Immunization Week, the Centers for Disease Control and Prevention (CDC) and global partners are promoting one of the world’s most powerful tools for health – the use of vaccines to protect people of all ages against disease. CDC works closely with a wide variety of partners in more than 60 countries to vaccinate children and provides scientific and technical support to ministries of health to strengthen and expand countries' capacities to sustain, monitor and evaluate their national immunization programs.

We recently met with Dr. Jacqueline Tate, an epidemiologist at CDC, who has been involved with rotavirus programs since the vaccine was first approved:

Dr. Jacqueline TateAs with many health professionals at Atlanta’s Centers for Disease Control and Prevention (CDC), the white walls of Dr. Jacqueline Tate’s office seem another world in comparison to places she often finds herself for work. As an epidemiologist for CDC’s viral gastroenteritis team, Dr. Tate is spending more of her time these days in countries impacted by rotavirus, despite the development in 2006 of an effective vaccine for this common but often deadly viral infection.

“A lot of our surveillance is in countries that haven’t started using the vaccine,” Dr. Tate said. “It’s not as widely used in a lot of the developing world.”

An intestinal virus that infects nearly all of the world’s children by the age of five, rotavirus is the most common cause of severe diarrhea among infants and young children worldwide. Though treatable with re-hydration salts, the effects of rotavirus infection can be deadly, particularly in developing countries where access to health care is limited and awareness about the virus is low. Worldwide, as many as 500,000 children die each year from gastroenteritis caused by rotavirus infection, a statistic Dr. Tate and her team are trying to change through support from the CDC Foundation.

Despite the introduction of the oral rotavirus vaccine, its use in much of the world’s developing countries is still limited, due in part to its relatively high cost, a limited understanding worldwide of the scale of the disease burden, and difficulties in accessing populations in remote areas. In 2009, the World Health Organization (WHO) recommended that the rotavirus vaccine be included in all national vaccination programs. While the vaccination is attributed to reduced rates of hospitalization among children in the United States and reduced rates of diarrheal mortality in Mexico, where diarrheal mortality rates dropped by as much as 40% once the vaccine became available, Dr. Tate and her team are monitoring a range of African countries to determine the impact of the vaccine once it becomes more widely available there. Of the 16 countries that applied for the vaccine in 2011, 12 are in Africa, where mortality rates among infected children are among the highest in the world.

“We’re not sure how effective the vaccine will be in Africa, so that’s why we’re working with the CDC Foundation to monitor the impact of the vaccine,” Dr. Tate said.

VaccinationHaving joined the CDC in 2006 – the year the rotavirus vaccine was approved – Dr. Tate says she recognized the unique opportunity that existed to come on board when the impact of the vaccination program was just being felt. By monitoring countries not yet using the vaccines, and studying the impact of the vaccination programs once they are introduced, Dr. Tate and her colleagues are able to improve the reach and impact of the vaccination programs through their recommendations – a unique opportunity for any infectious disease professional.

“It’s exciting because this is one of the shortest lags between when a vaccine becomes available and when it’s rolled out in developing countries,” Dr. Tate said. “Almost half a million kids die worldwide each year from rotavirus, so now we have the tools to prevent that.”

Learn more about CDC’s work with rotavirus.

Learn more about why CDC is committed to global immunization.

Learn more about the CDC Foundation’s rotavirus projects and work in Global Health.

Terri Heyns, MA, is the associate vice president for communications for the CDC Foundation.