Dengue infection during pregnancy in Burkina Faso: a cross-sectional study

Abstract

Background:
Dengue fever is prevalent in the world; in recent years, several outbreaks occurred in West Africa. It affects pregnant women. We aimed to assess the consequences of dengue fever on pregnant women and their fetuses during dengue epidemic in Burkina Faso.

Methods:
We conducted a cross-sectional study from November 1, 2015 to January 31, 2017 in 15 public and private health facilities in Ouagadougou, using secondary data. Immunochromatographic rapid test Duo detecting specific antibodies, immunoglobin M/G and /or dengue non structural antigen1 virus was used to diagnose dengue cases.

Results:
Out of 399 (48%) women registered during the study period, 25 (6%) were pregnant. The average age of pregnant women was 30 years, with 18 and 45 years as extremes. The main symptoms were fever (92%) and headache (92%). Nine patients (36%) had severe dengue characterized by bleeding (16%), neurological symptoms (16%) and acute respiratory distress (8%). Eight (32%) of the 25 women had early miscarriage and 8 (32%) women gave birth to viable fetuses. Among those with viable babies, 5 (20%) presented post-partum hemorrhage and 3 (12%) presented early delivery. The main fetal complications included 3 cases of acute fetal distress (12%). One case of maternal death (4%) and 4 cases of neonatal mortality (44.5%) were notified.

Conclusion:
Dengue fever occurring during pregnancy increases maternal and neonatal mortality. Its severe complications require specific monitoring of pregnant women until delivery.

Full text

R E S E A R C H A R T I C L E Open Access
Dengue infection during pregnancy in
Burkina Faso: a cross-sectional study
Kongnimissom Apoline Sondo
1,2*
, Adama Ouattara
1,3
, Eric Arnaud Diendéré
2
, Ismaèl Diallo
1
, Jacques Zoungrana
4
,
Guelilou Zémané
2
, Léa Da
2
, Arouna Gnamou
2
, Bertrand Meda
5
, Armel Poda
4
, Hyacinthe Zamané
1,3
,
Ali Ouédraogo
1,3
, Macaire Ouédraogo
4
and Blandine Thieba/Bonané
1,3
Abstract
Background: Dengue fever is prevalent in the world; in recent years, several outbreaks occurred in West Africa. It
affects pregnant women. We aimed to assess the consequences of dengue fever on pregnant women and their
fetuses during dengue epidemic in Burkina Faso.
Methods: We conducted a cross-sectional study from November 1, 2015 to January 31, 2017 in 15 public and private
health facilities in Ouagadougou, using secondary data. Immunochromatographic rapid test Duo detecting specific
antibodies, immunoglobin M/G and /or dengue non structural antigen1 virus was used to diagnose dengue cases.
Results: Out of 399 (48%) women registered during the study period, 25 (6%) were pregnant. The average age of
pregnant women was 30 years, with 18 and 45 years as extremes. The main symptoms were fever (92%) and headache
(92%). Nine patients (36%) had severe dengue characterized by bleeding (16%), neurological symptoms (16%)
and acute respiratory distress (8%). Eight (32%) of the 25 women had early miscarriage and 8 (32%) women
gave birth to viable fetuses. Among those with viable babies, 5 (20%) presented post-partum hemorrhage and 3 (12%)
presented early delivery. The main fetal complications included 3 cases of acute fetal distress (12%). One case
of maternal death (4%) and 4 cases of neonatal mortality (44.5%) were notified.
Conclusion: Dengue fever occurring during pregnancy increases maternal and neonatal mortality. Its severe
complications require specific monitoring of pregnant women until delivery.
Keywords: Dengue fever, Pregnant woman, Burkina Faso
Background
Dengue is an arboviral infection transmitted by mosqui-
tos of the genus Aedes [1,2]. The incidence of dengue
has increased by a factor of 30 over the past 5 decades,
with the emergence of many new affected countries [2].
About 2.5 billion people live in endemic areas and an
estimated 50 million people are infected each year [1–3].
The disease can affect anyone but pregnant women are
more at risk. The most common clinical symptom of
dengue is fever that can cause abortion or early delivery.
Dengue-related thrombocytopenia increases the risk of
bleeding during pregnancy or at delivery, and therefore
leads to higher maternal mortality rate.
Studies on the reciprocal influence between dengue
and pregnancy are quite rare. The fetal consequences of
dengue are neither well understood nor well docu-
mented [4]. Few data on dengue during pregnancy exist.
Authors reported some cases in Asia, Europe or Latin
America [1,5,6]. In sub-Saharan Africa, it was urgent to
assess the extent of the disease. In Burkina Faso as in
other sub-Saharan countries, dengue cases have been
reported since 2013, with an outbreak in 2016. The
objective of this survey was to describe the socio-
epidemiological, clinical, biological aspects, and the
evolution of dengue during pregnancy in Ouagadougou.
© The Author(s). 2019 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0
International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and
reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to
the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver
(http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
* Correspondence: sondoapoline@yahoo.fr
1
Joseph Ki-Zerbo University, Ouagadougou, Burkina Faso
2
Department of Infectious Diseases (Yalgado Ouedraogo Teaching Hospital),
Ouagadougou, Burkina Faso
Full list of author information is available at the end of the article
Sondo et al. BMC Infectious Diseases (2019) 19:997
https://doi.org/10.1186/s12879-019-4587-x
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Methods
This was a descriptive cross-sectional study involving 15
health facilities in the city of Ouagadougou: 4 District
hospitals and 3 Teaching hospitals with packages of
healthcare services corresponding to the secondary and
tertiary levels of the health pyramid in Burkina Faso. In
addition, eight private health facilities were selected
according to their capacity of diagnosing dengue to be
part of the study. We obtained the authorization of the
General Director of Healthcare in Ouagadougou for data
collection. The diagnosis of dengue was performed using
rapid diagnostic tests (RDTs), which are immuno-
chromatographic tests detecting Non Structural Antigen
1 (NS1Ag) and immune-globulin M and G (IgM and
IgG). We used the World Health Organization classifica-
tion of dengue (WHO 2009) to classify the women
according to the severity of dengue.
The study population consisted of all the patients
(male and female) diagnosed with dengue in these
healthcare centers from November 1, 2015 to January
31, 2017, using dengue RDTs.
The sample consisted of all the pregnant women
treated for dengue in these healthcare centers. The
inclusion criteria were the positivity of the NS1 antigen
and/or IgM and/or IgG. Isolated IgG positivity was
considered a serological scar of dengue but we could not
titrate this antibody.
Serotype 2 of dengue virus (DENV-2) was identified by
Polymerase chain reaction (PCR) in the Pastor Institute
of Dakar, as the causal agent of the epidemic during the
study period [7].
The diagnosis of malaria was performed using malaria
RDTs Histidine Rich Protein 2 and / or blood smears.
The data were collected from the consultation records,
laboratories and the clinical records of the patients.
The collected data were analyzed using EPI INFO
version 3.5.
Results
Socio-epidemiological characteristics of pregnant women
In this study, 835 patients were screened for dengue,
using rapid diagnostic tests (RDTs). Among them, there
were 399 women (48%), including 25 (6.5%) pregnant
women. Sixty-eight percent of the pregnant women were
between the ages of 25 and 35 years. The average age of
pregnant women was 30 years with 18 and 45 years as
extremes, and 92% of pregnant women lived in
Ouagadougou. Forty four percent (44%) had university
degrees and 36% high school level. Thirty-wo percent
(32%) were public and private sectors workers. Students
accounted for 24%, as did housewives, and 20% of
women were informal sector workers. Dengue frequency
distribution during the study period showed a peak in
October with 10 cases (40%), which corresponds to the
peak in all the patients. Eight cases (32%) were notified
in November 2016 (Fig. 1).
Clinical and biological characteristics of pregnant women
Among the pregnant women diagnosed with dengue, 8
were in their first trimester of pregnancy, 8 in their
second trimester and 9 in their third trimester.
The reported clinical symptoms were fever (92%),
asthenia (64%) and painful symptoms (84%) including
headaches (92%), arthralgia (72%) and lumbago/myalgia
(64%). Hemorrhagic signs (32%) included epistaxis (24%)
and metrorrhagia (16%). Four women (16%) presented
neurological symptoms such as consciousness disorders
(coma stage I = 1 case and coma stage II = 3 cases). Two
cases of malaria-dengue co-infection were notified. The
clinical characteristics of women are shown in Table 1.
Twenty-one of the 25 pregnant women (84%) had early
dengue with positive NS1Ag. Sixteen pregnant women
(64%) presented with primary dengue and 6 others (36%)
with secondary dengue fever. Three patients were carriers
of IgG alone.
Fifteen pregnant women (52%) had anemia with
hemoglobin level less than 10 g/dl. Two of them were
transfused with packed red blood cells. Thrombocytopenia
defined as platelet count less than 150,000 / mm3, was
observed in 12 patients (48%). Six of them had platelet
count less than 50,000 / mm3 and 5 women received
transfusion of platelets. Six women (24%) had elevated
levels of aspartate aminotransferase (ASAT) ranging from
2 to 15 times the normal value. Two patients had a serum
creatinine higher than 120 μmol/l.
Sixteen women (64%) had dengue fever with warning
signs while 9 women (36%) had severe dengue fever, ac-
cording to the 2009 WHO classification.
Maternal and fetal consequences
In mothers
Maternal complications were present in 6 cases. There
was early delivery in 3 cases (12%) and intra partum
hemorrhage in 5 cases (20%). Three women gave birth
vaginally while 3 others underwent caesarean section.
Two women expelled macerated fetuses. Seventeen
women were always pregnant while they were discharged,
and 8 women gave birth, with one of them having twins.
A death was recorded in a context of liver failure and
postpartum hemorrhage, which stands for 4% of lethality.
Lethality was 12.5% among those who gave birth.
In fetuses and newborns
Fetal complications were observed in 6 cases including 3
cases (12%) of fetal distress and 3 cases (12%) of prema-
turity. Four cases of neonatal deaths (44.5%) were noti-
fied, 3 of which were due to prematurity and one case to
Sondo et al. BMC Infectious Diseases (2019) 19:997 Page 2 of 5
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neonatal infection. Women and fetal consequences are
summarized in Table 2.
Discussion
During the study period, 25 pregnant women were
infected by dengue virus in Ouagadougou. The monthly
epidemiological curve showed a maximum number of
cases in October and November. The proportion of
pregnant women with dengue was probably underesti-
mated during our study as we only described the cases
present in our database and as the survey was conducted
in facilities not frequented by all pregnant women. Den-
gue surveillance should be instituted in pregnant women
in order to distinguish it from malaria, since the two
diseases share many common symptoms. The patients’
average age was 30 years, close the result of a descriptive
survey conducted in Rio de Janeiro [8], and lower than
the results found in other series in French Guiana [9]
and Malaysia [5]. The disparity in the age of pregnant
women could be justified by the fact that the average
age of first maternity differs from one country to an-
other, by sociocultural differences, and development
level differences.
Unlike the common situation in developing countries
where most of women suffering from infectious diseases
are unemployed, housewives or farmers, most of preg-
nant women in our series were public and private
sectors workers. Therefore, most of them could afford
for the rapid diagnostic test cost (15 to 25 euros). This
fact shows that pregnant women from low socioeco-
nomic categories (housewives, farmers, unemployed)
suffering from dengue but unable to afford for RDTs
cost could not be diagnosed. The dengue frequency in
pregnant women was underestimated, regarding the
2016 dengue outbreak in the city of Ouagadougou [7].
Fig. 1 Distribution of dengue cases in pregnant women by month
Table 1 Distribution of cases according to clinical aspects
Clinical aspects Frequency (%)
Stage of pregnancy
First trimester 08 (32)
Second trimester 08 (32)
Third trimester 09 (36)
Clinical signes
Fever 23 (92)
Painfull signs 21 (84)
Headaches 23 (92)
Arthralgia 18 (72)
Myalgia 16 (64)
Abdominal pain 12 (48)
Retro-orbicular pain 04 (16)
Asthenia 16 (64)
Vomiting 14 (56)
Hemorrhagic signs 08 (32)
Epistaxis 06 (24)
Metrorrhagia 04 (16)
Gingivorragia 03 (12)
Other
a
04 (16)
Neurologics signs 04 (16)
Comatose stage II 02 (8)
Comatose stage I 02 (8)
Jaundice 03 (12)
Hépatomegaly 03 (12)
Dyspnea 02 (8)
Oligoanuria 02 (8)
Plasma leak (pleurisy) 01 (4)
Lithiasis 01 (4)
a
= Hematemesis, hematuria, melena, hemorrhagic at the injection site
Sondo et al. BMC Infectious Diseases (2019) 19:997 Page 3 of 5
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Out of the 25 pregnant women infected by dengue in
our study, 84% were at phase of viremia. In Colombia, a
reverse situation was observed in two studies with an
acute viremic phase of 29.9 and 27.3% [6,10]. In our
context, dengue diagnosis was performed early com-
pared to other authors’results because of the epidemic
context. About 9 cases of probably secondary dengue
were observed, showing that these patients had caught a
previous infection by dengue virus; that could explain
the high proportion of severe mother and child compli-
cations (24 and 20% respectively). On the other hand,
this high proportion of complications in Sub Saharan
Africa contrasts with the results reported by some au-
thors who suggested that being black was a protective
factor and could explain the low proportions of severe
dengue notified in African series [7,11,12].
In our study, the reported cases showed an upward
distribution according to the trimester of pregnancy,
with a doubling of the number of cases from the 1st to
the 3rd trimester. Similar findings were reported in
Colombia [13]. However, some authors reported higher
infection frequency during the first trimester of pregnancy
(45.4%) [10]. Carles in French Guiana found a higher
incidence of the infection during the second trimester
(40.9%) [14]. The period of occurrence of dengue seems to
determine the types of complications, to the point that
pregnant women infected during their first trimester had
higher risk of miscarriage [3,15]. When the infection
occurred during the last trimester, the risk of low birth
weight, premature labor and vertical transmission seemed
to be higher [3,8,13,16]. However other factors could
explain the low birth weight as well as the prematurity. In
our series, the evolution and the outcome of the pregnan-
cies of women infected in their first and second trimester
were not taken into account. However, out of 9 women in
their third trimester of pregnancy, we observed 8 deliver-
ies during the acute stage of dengue, with delivery bleed-
ing 5/25 (20%) and prematurity 3/8 (12%). Almost half
(45.5%) of the 9 newborns died. In the literature, there is a
high percentage of threating preterm delivery, as shown in
series conducted in Malaysia (50%) [5] and French Guiana
(55%) [13]. A study in Cuba reported a risk of preterm
delivery 3.7 times higher than in our series [17]. A specific
management of pregnant women with dengue fever, espe-
cially in the last trimester, could reduce the risk of prema-
turity and prevent the risk of bleeding during delivery.
In our study, we recorded only 3 cases of Caesarean
section out of the eight deliveries. Most of the studies
reported as many cases of Caesarean section as natural
deliveries; for instance, Alvarenga and Leon reported 50
and 53.8% respectively [8,18]. Considering the high risk
of bleeding in pregnant women with dengue, caesarean
section practice would reduce the incidence of postpar-
tum bleeding.
We recorded one maternal death out of 25 cases. Ma-
ternal mortality is significant in most studies: 17/78 in
Sudan, 2/13 in Rio de Janeiro, and 3/16 in South Asia [5,
8,19]. The recorded case of death in our series occurred
in a context of complications, similarly to the situation
reported by Machado in Brazil who found that pregnant
women were 3.4 times more susceptible to catch severe
dengue, and that dengue-related mortality in pregnant
women was higher than in non-pregnant women [20,
21]. Therefore, any pregnant woman diagnosed with
dengue must be considered as having a high risk of
developing severe dengue. Such women require rigorous
medical surveillance.
Conclusion
Our study showed that pregnant women are at high risk
of complications when they catch dengue fever. The
usual bleeding during delivery may be aggravated by this
disease. On the other hand, some of the complications
noted in this study cannot be exclusively attributed to
dengue fever. Nevertheless, these complications should
be taken into account in order to prevent the risk of
bleeding and preterm delivery.
Table 2 Maternal and perinatal outcomes
Item Frequency (%)
Mother outcome
Death 1 (4)
Exit without medical advice 1 (4)
Maternal death (n= 8: known outcome) 1 (12,5)
Pregnancy outcome
Normal pregnancy 17 (56)
Delivery
a
8 (36)
Normal vaginal delivery (living newborn) 3 (12)
Preterm delivery (macerated dead fetus) 2 (8)
Caesarean section 3 (12)
Living newborns (n= 9 birth) 5 (55.5)
Dead (n = 9 birth) 4 (44.5)
Death in-utero 2 (8)
Perinatal death 2 (4)
Maternal complications 6 (24)
Hemorrhagic delivery
b
5 (20)
Preterm delivery 3 (12)
Dynamic dystocia 2 (8)
Fetal complications 5 (20)
Fetal distress 3 (12)
Prematurity 3 (12)
Néonatal infections 2 (8)
a
= Eight deliveries with 9 children: one twin birth
b
delivery bleedi ng (4) and parietal hematoma after cesarean section = 1
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Abbreviations
ASAT: Aspartate aminotransferase; IgG: Immunoglobin G; IgM: Immunoglobin
M; NS1Ag: Non Structural Antigen 1; PCR: Polymerase Chain Reaction;
RDTs: Rapid Diagnostic Tests; WHO: World Health Organization
Acknowledgements
We thank the regional director of health of Ouagadougou for having
authorized this study, the heads of the facilities included in the studies,
(public and private health facilities in Ouagadougou city), and all those who
took part in the study. This research was presented at the 6th Congress of
the African Society of Infectious Pathology in Dakar (Senegal 2017).
Authors’contributions
SKA, OA, DEA and ID designed the study, wrote the research protocol,
collected and analyzed data, and wrote the manuscript. ZG, GA, DL and ZH
collected data. ZJ, PA, and MB provided the bibliography. OA, TBB and OSM
directed the study, gave a critical reading and final correction of the article.
All authors read and approved the final manuscript.
Funding
The study did not receive any funding. Not applicable.
Availability of data and materials
The data used during the study are available from the corresponding author.
Ethics approval and consent to participate
It is a retrospective study based on data collected from patients’clinical
records, authorized by the regional director of the health of Ouagadougou.
Consent for publication
Not applicable
Competing interests
The authors declare that they have no competing interests.
Author details
1
Joseph Ki-Zerbo University, Ouagadougou, Burkina Faso.
2
Department of
Infectious Diseases (Yalgado Ouedraogo Teaching Hospital), Ouagadougou,
Burkina Faso.
3
Obstetrics and Gynecology Departement (Yalgado Ouedraogo
Teaching Hospital), Ouagadougou, Burkina Faso.
4
Higher Health Science
Institute, Polytechnic University of Bobo-Dioulasso, Burkina, Faso.
5
Health
Science Research Institute of Ouagadougou (Biomedical department),
Burkina, Faso.
Received: 24 January 2018 Accepted: 22 October 2019
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