Seroprevalence of measles vaccine antibody response in vertically HIV-infected children, in Morocco

Houda Haban,Soumia Benchekroun,Hicham Oumzil,Elmir Elharti,Said Amzazi,Mina Sadeq,Abdelaziz Benjouad,Hinda Jama Ahmed,Latifa Tajounte

doi:10.1186/s12879-018-3590-y

Abstract

BackgroundThe widespread use of an effective and safe vaccine to measles has substantially decreased morbidity and mortality from this epidemic. Nevertheless, HIV-infected children vaccinated against measles may develop an impaired vaccine response and remain susceptible to this disease. In Morocco, infants are routinely vaccinated against measles, regardless of their HIV serostatus. An evaluation of the immunization of these children may be of paramount importance to implement timely measures aimed at preventing measles transmission.MethodsIn this study, we have enrolled 114 children vaccinated against measles, 50 children prenatally infected with HIV and 64 HIV-uninfected children. For all children, blood samples were taken to measure anti-measles IgG by EIA and CD4 count by flow cytometry. Additionally, HIV viral load was determined by automated real time PCR, for HIV-infected children.ResultsThe seroprotective rate of IgG anti-measles antibodies was significantly lower among HIV-infected children (26%) compared with HIV-uninfected children (73%) (p < 0.001). Within HIV-infected children group, the comparison of variables between children without seroprotective seroconversion to measles and those with seroprotective immunity, displayed that sex and age were not statistically different, p > 0.999 and p = 0.730, respectively. However, CD4 count was lower among children with negative serostatus to measles (23% versus 32%, p < 0.001). Furthermore, viral load was higher, with 2.91 log10 ± 2.24 versus 1.7 log10 ± 1.5 (p = 0.042). Finally, 62% of children with a negative vaccine response to measles were under HAART therapy, versus 92% (p = 0.008).ConclusionThe majority of HIV-infected children vaccinated against measles develop a suboptimal seroprotective titer, and therefore remain at risk for this highly infectious disease. These data in combination with international recommendations, including recent WHO guidance on vaccination of HIV-infected children, suggest there is a need for national measures to prevent these children from measles.

Highlights

The widespread use of an effective and safe vaccine to measles has substantially decreased morbidity and mortality from this epidemic
Measles are highly contagious paramyxoviruses, which cause substantial mortality among children and even adult. This disease is vaccine preventable, and the widespread use of effective and affordable vaccine has brought about a significant drop of the burden of measles epidemic [1,2,3,4]
Measles vaccine is known to produce protective levels of antibodies in more than 90% among immunocompetent children [24, 25]. When it comes to HIV-infected children, low immunogenicity and ongoing decay of measles antibodies are the hallmark of this vaccine response [26, 27]

Summary

Introduction

The widespread use of an effective and safe vaccine to measles has substantially decreased morbidity and mortality from this epidemic. HIV-infected children vaccinated against measles may develop an impaired vaccine response and remain susceptible to this disease. Measles are highly contagious paramyxoviruses, which cause substantial mortality among children and even adult. This disease is vaccine preventable, and the widespread use of effective and affordable vaccine has brought about a significant drop of the burden of measles epidemic [1,2,3,4]. In 2015, the number of reported measles cases was 21,335 This epidemiological situation was attributed to important outbreaks in countries with political instability and conflicts, mainly countries that have experienced the “Arab Spring” [5, 8]. The WHO goal to eliminate measles in this region, was deferred to 2020 [9]

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Results

Conclusion