Measles immunity among pregnant women aged 15–44 years in Namibia 2008 and 2010

Friday, 9th of September 2016

Measles immunity among pregnant women aged 15–44 years in Namibia 2008 and 2010

Cristina V. Cardemil

 

Anna Jonas

 

Anita Beukes

 

Raydel Anderson

 

Paul A. Rota

 

Bettina Bankamp

 

Howard E. Gary Jr

 

Souleymane Sawadogo

 

Sadhna V. Patel

 

Sikota Zeko

 

Clementine Muroua

 

Esegiel Gaeb

 

Kathleen Wannemuehler

 

Sue Gerber

 

James L. Goodson

Corresponding Editor: Eskild Petersen Aarhus Denmark.

 

Background

Namibia experienced a large measles outbreak starting in 2009 with 38% of reported cases in adults including women of reproductive age. Population immunity was assessed among pregnant women to determine whether immunization activities were needed in adults to achieve measles elimination in Namibia.

Methods

A total of 1708 and 2040 specimens sampled from Namibian pregnant women aged 15–44 years who were included in the 2008 and 2010 National HIV Sentinel Survey respectively were tested for measles immunoglobulin G antibody. The proportion of women seropositive overall and by 5-year age strata was determined and factors associated with seropositivity were analyzed by logistic regression including age facility type gravidity HIV status and urban/rural setting. Seropositivity in 2008 versus 2010 was compared.

Results

In both analysis years measles seropositivity was lower in 15–19-year-olds (77%) and 20–24-year-olds (85–87%) and higher in 25–44-year-olds (90–94%) (2008 p < 0.001; 2010 p < 0.001). Overall measles seropositivity did not differ between 2008 (87%) and 2010 (87%) (p = 0.7). HIV status did not affect seropositivity.

Conclusions

Late in a large measles outbreak 13% of pregnant women in Namibia and almost one in four 15–19-year-old pregnant women remained susceptible to measles. In Namibia immunization campaigns with measles-containing vaccine should be considered for adults.