International Journal of Infectious Diseases
August 2015 Volume 37, p1
Middle East Respiratory Syndrome – need for increased vigilance and watchful surveillance for MERS-CoV in sub-Saharan African Africa
Alimuddin Zumla, Roxana Rustomjee, Francine Ntoumi, Peter Mwaba, Matthew Bates, Markus Maeurer, David S. Hui, Eskild Petersen
Published online: June 30 2015
The past two decades have witnessed the emergence of several new and old respiratory tract infectious diseases, which threaten global health security due to their epidemic potential.1,2 These include multi-drug resistant TB, Severe Acute Respiratory Syndrome (SARS), avian and swine influenza and more recently the Middle East Respiratory Syndrome (MERS). MERS is a new zoonotic disease of humans caused by a coronavirus (MERS-CoV) which was first isolated in September, 2012 from a patient who died from a severe respiratory disease in Jeddah Saudi Arabia.
Outbreak of varicella in a highly vaccinated preschool population
Jiye Fu, Juguang Wang, Chu Jiang, Rujing Shi, Tianwei Ma
Beijing Haidian Center for Disease Control and Prevention, NO.5 Xibeiwang 2nd Road, Haidian district, Beijing 100094, People’s Republic of China
Corresponding Editor: Eskild Petersen, Aarhus, Denmark
:: Breakthrough varicella may be as infectious as varicella in unvaccinated persons.
:: The potential for transmission due to breakthrough varicella should be focused on.
:: No increased risk for breakthrough varicella was found in 1-dose vaccine recipients.
:: High 1-dose varicella vaccination coverage is not sufficient to prevent outbreak.
:: To control varicella outbreak, a second dose may deserve additional consideration.
Varicella vaccine is available for private purchase in Beijing, with single dose recommended for children aged ≥12 months before 2013. Despite the success achieved in reducing varicella incidence, varicella outbreaks continued to occur, including in schools and kindergartens among highly vaccinated children. We investigated a varicella outbreak in a preschool with high varicella vaccination coverage in Haidian district, Beijing.
Through questionnaires, data including children’s medical and vaccination history were collected from their parents. A case of varicella was defined as an acute, generalized, maculopapulovesicular rash without other apparent cause in a child in the preschool from March 10 through March 29, 2010. Attack rates in vaccinated and unvaccinated children were calculated, and the analyses of vaccine effectiveness (VE) and of risk factors for breakthrough disease (varicella occurring >42 days after vaccination) were conducted.
A total of 12 cases occurred during the outbreak, and ten of them (83.3%) had breakthrough varicella. The index case with mild varicella occurred in a child who had been vaccinated four years previously. Questionnaires were returned for all of 150 children in the preschool. Of all the 150 children, 144 (96.0%) had no prior history of varicella disease. Among these children, 135(93.7%) had received single-dose varicella vaccine before the outbreak. VE was 84.5% [95% confidence interval (CI): 62.8%∼93.5%] in preventing varicella of any severity, and VE was 92.2% (95% CI: 81.4%∼96.8%) against moderate to severe varicella. Age at vaccination (<15 months vs. ≥15 months) and time since vaccination before the outbreak (<3 years vs. ≥3 years) were not associated with the increased risk of breakthrough varicella(P=0.124 and 1, respectively). All the varicella cases with vaccination history verified through immunization records had received varicella vaccine and measles-mumps-rubella vaccine >30 days apart.
Breakthrough infection with fever in vaccinated person may be as infectious as varicella in unvaccinated persons. High single-dose varicella vaccination coverage is effective in reducing varicella incidence, but not sufficient to prevent outbreak. To control varicella outbreak a second dose may deserve additional consideration.