Seroprevalence of Pandemic (H1N1) 2009 in Pregnant Women in China: An Observational Study

2011

Seroprevalence of H1N1 in Pregnant Women in China

Sample size: 1040 publication 10 minutes Evidence: moderate

Author Information

Author(s): Huo Xiang, Qi Xian, Tang Fenyang, Zu Rongqiang, Li Liang, Wu Bin, Qin Yuanfang, Ji Hong, Fu Jianguang, Wang Shenjiao, Tian Hua, Hu Zhibin, Yang Haitao, Zhou Minghao, Wang Hua, Zhu Fengcai

Primary Institution: Jiangsu Provincial Center for Disease Prevention and Control, Nanjing, China

Hypothesis

What are the seropositive rates and persistence of antibodies against pandemic (H1N1) 2009 virus in pregnant women and voluntary blood donors after the second wave of the pandemic?

Conclusion

The study found that seropositive rates for H1N1 antibodies declined significantly in both pregnant women and blood donors after the pandemic.

Supporting Evidence

The seropositive rates in pregnant women were initially above 50% but dropped to about 20% after 15 weeks.
A significant decline in seropositive rates was observed across four sampling times.
The correlation between antibody titers against pH1N1 and seasonal H1N1 was statistically significant.

Takeaway

This study looked at how many pregnant women and blood donors had antibodies against the H1N1 virus after the pandemic, and it found that many had them, but those numbers went down over time.

Methodology

Serum samples were collected from 720 unvaccinated pregnant women and 320 voluntary blood donors, and tested for antibodies against pH1N1 using hemagglutination inhibition assay.