Pneumonia of Children under 5 Years of Age in Brazzaville ( Republic of Congo )

Pneumonia is one of the prime causes of morbidity and mortality in children under five years of age. Objectives: To determine the frequency of pneumonia, to identify the causative organisms and the factors associated with death in children under 5 years of age. Methods: A prospective cohort study was performed in children 1 to 59 months hospitalized for pneumonia between January and June 2016 in CHUB pediatric wards. Results: A total of 237 children were hospitalized for pneumonia, i.e. 12.3% of hospitalizations. There were 133 boys (56%) and 104 girls (44%) with a mean age of 15.9 ± 13.8 months. The average time elapsed between onset of symptoms and hospitalization was 7.2 ± 6.1 days. The alveolar syndrome 185 cases (81%), alveolo-interstitial 34 cases (15%), alveolar and pleural 9 cases (4%) were the main radiological translations. Blood cultures were positive in 74 cases (31%) and the bacteria identified were: Streptococcus pneumoniae 42 cases (17.5%), Staphylococcus Aureus 23 cases (9.6%) and Klebsiella pneumoniae 9 cases (3.7%). HIV serology was positive in 19 cases (8%). Fifty-eight (58) children (24%) died. Factors associated with death were respiratory distress, hypoxemia and hypothermia. Conclusion: Pneumonia of children under 5 years of age is frequent and severe prognosis. Their mastery requires the strengthening of the national respiratory disease control program and the knowledge of risk factors.

Pneumonia can be prevented by vaccination and its mortality reduced with the implementation of the WHO strategy [1] for the management of Acute Respiratory Infections (ARI) in children under five years of age.This is based on early clinical screening and rational use of antibiotic therapy in primary and peripheral hospitals.
In the Congo, the prevalence of pneumonia is not known, nor there is a system for the epidemiological surveillance of respiratory diseases in children.However, respiratory emergencies are the second leading cause of hospitalization in children under 5 years of age, according to the study by Moyen et al. [9].
This first Congolese study aimed to determine the frequency of pneumonia and to identify the causative germs and factors associated with death in children under 5 years of age in Brazzaville.

Methodology
This was a prospective cohort study conducted between January and June 2016 at the University Hospital of Brazzaville (UHB) in the Republic of Congo.The population of Brazzaville was estimated at 1,373,382 inhabitants in 2015, the climate is tropical with an average annual temperature of 25.5˚C.
Children aged 1 to 59 months admitted to the pediatric wards during the study period, meeting the diagnostic criteria for pneumonia, were included.Parental consent was required and obtained to be eligible.The diagnostic criteria of the pneumonia selected were those defined by the WHO [10]: pneumonia is said to have no sign of severity when breathing is rapid (≥60 cycles per minute in children less than 2 months, ≥50 cycles per minute between 2 and 11 months and ≥40 cycles per minute between 1 and 5 years) associated with crackling rats on auscultation.Pneumonia is said to be severe when, at the signs of pneumonia without signs of gravity, a draw is associated.Pneumonia is said to be very severe when severe pneumonia is associated with central cyanosis, inability to drink or nurse, incoercible vomiting, convulsions, lethargy or loss of consciousness, severe respiratory distress.
Children with chronic cough were not included in the haunting of tuberculosis.
The variables analyzed were:  Epidemiological: -Those related to parents: age, educational level, socio-economic level, number of adults sleeping in the same room as children under prior to hospitalization, vaccination status for pneumococcal antigens and Haemophilus influenzae b, feeding for the first six months, the existence of a particular terrain such as HIV/AIDS, sickle cell disease, heart disease, diabetes. Clinic: The state of consciousness, temperature, color, respiratory rate, moisture state, nutritional status, signs of pulmonary auscultation, percutaneous oxygen saturation and the existence of hepatomegaly and/or splenomegaly. Paraclinic: The radiograph of the thorax, interpreted by two paediatricians, with confirmation in each case by a radiologist, a hemogram, C-reactive protein, retroviral serology (HIV) and blood culture whose technique was as follows: After sampling of blood on culture medium, an incubation in the oven at 37˚C.In the BacT-Alert 3D automaton was carried out for five days.Beyond that, the bacteria detected were contaminants.The inoculum was seeded in the following culture media: cooked blood agar supplemented with poly vitex for the growth of Streptococcus pneumoniae and Haemophilus Influenzae, fresh (human) blood culture agar for streptococcus culture, Chapman medium for culture of staphylococci.Microscopic analysis was performed using Gram staining, identification and antibiogram were performed by the Compact 2 raptor.Quality control was performed using the reference strains recommended by CA-SFM/EUCAST for: Streptococcus pneumoniae ATCC 49616, Staphylococcus aureus ATCC 29213 and Klebsiella pneumoniae ATCC 700603.

 Therapeutic and Evolutionary
Treatment during hospitalization, length of hospital stays, observed complications, and type of progression (favorable outcome, progression to death or complications).

Definitions of Concepts
-The socio-economic level was assessed on the basis of the food poverty line defined by the National Congolese Center for Statistics and Economic Studies (CNSEE) [11]: it is said to be low when the family spends less than 523 FCFA (African Financial Community Franc/CFA. 1 Dollar = 550 CFA Francs =) per person per day, average between 523 and 1685 CFA francs and raised between 1685 and 5055 CFA francs.
-Hypoxemia was retained when the oxygen saturation was less than 90%.
-Nutritional status was assessed on the basis of WHO growth standards [12].
-The typology of the radiological images was made by referring to the WHO standardized criteria [13].
-For HIV serology, presumptive diagnosis in infants under 18 months of age was retained when the infant met the following criteria: signs suggestive of HIV infection [14], the positivity of its serology and that of his mother -The cough was called chronic for a duration greater than or equal to 1 month.
-Vaccination was up-to-date when the child received 3 doses of both vaccine serotypes (PCV13 and HI b).
-Polypnea was defined as fast breathing (≥60 cycles per minute in children less than 2 months of age, ≥50 cycles per minute between 2 and 11 months and ≥40 cycles per minute between 1 and 5 years of age.
-Hypothermia was defined as a temperature below 35˚C.
-Promiscuity has been defined by the existence of more than three persons other than the child under 5 years of age.

Ethical Considerations
The study protocol obtained the approval of the Committee of Ethics of Health Sciences Research: N 041/MRSIT/IRSSA/CERSSA.

Statistical Analysis
Data was entered using CS Pro and SPSS ® 16.Percentages, averages and standard deviations were calculated.In order to assess the influence of age on certain variables and to identify the determinants of pneumonia-related mortality, an analytical study was carried out with relative risk (RR) and confidence interval (CI) to 95%.In order to identify the factors associated with mortality, some variables were adjusted on others to eliminate the confounding factors, thus allowing the calculation of the adjusted RR * by the Logit method.The statistical influence observed between two variables was assessed by the Pearson chi-square test, the significance level of the comparisons was <0.05. 1) 2) Epidemiological Aspects -Frequency, age and sex During the study period, 1934 children under 5 years were hospitalized, 237 of whom were pneumonia (12.3%).Pneumonia was the third leading cause of hospitalization after malaria and bronchiolitis.There were 133 boys (56%) and 104 girls (44%), with an average of 15.9 ± 13.8 months extremes (1 and 59 months).
-Living conditions of children: living conditions are recorded in Table 2 The signs of examination are given in Table 3, the classification of pneumonia according to the stage of severity, and the age and severity of pneumonia in Ta-   There was a favorable outcome for 179 children (76%), a complication was observed in 11 children (4%) with favorable outcome, pleural effusion 8 cases (3%) and pulmonary emphysema 3 cases (1%).The mean hospital stay was 6.5 ±

days (1 hour and 23 days).
The trend was towards one death in 58 children (24%).

6) Factors associated with mortality of pneumonia
The determinants of pneumonia mortality are shown in Table 5 and the factors associated with death in Table 6.

Discussion
The study of the pneumonia of children under 5 years in Brazzaville shows that these are frequent: 12.3% of the hospitalizations and third cause of hospitalization.They are observed in children vaccinated against pneumococcus 80.6% and Haemophilus influenzae 85.6%.Wasting is noted in 15.6%, and severe wasting in 8.9%.HIV serology is positive in 8%.
When the blood culture is positive, Streptococcus Pneumoniae and Staphylococcus Aureus are the main germs.Very severe pneumonia is more common in infants younger than 24 months (n = 39 (88.6%);P = 0.03).The evolution is severe: 24% of deaths.Factors associated with death from pneumonia include respiratory distress, hypothermia and oxygen saturation below 90%.

1) Epidemiological Data
The incidence of pneumonia was estimated at 12.3% in this study.However, it was not possible to compare this frequency because of the absence of the prior known incidence of pneumonia in the Congo and the absence of an epidemiological surveillance system for respiratory diseases.However, the EDS-Congo, 2012 [15] reports a 5% prevalence of ARI among children under 5 years of age.In the Gambia [16], the incidence of pneumonia is 280‰.
The mean age of onset of pneumonia, which varies according to authors [19], is between 11.7 and 19.7 months.The common denominator concerning age is that it is within 24 months [6] [7] [8].The high prevalence of pneumonia in children under 24 months of age is explained by the immaturity of the immune system of the first two years of life.
The masculine predominance found in this work is a known fact [20].However, in-depth studies would be needed to identify the determinants of this. 2

) Diagnosis of Pneumonia
The signs suggestive of pneumonia, classical [10], are as noted in this work: fever, crackling rales, respiratory discomfort and cough.But it is known that the absence of cough does not exclude the diagnosis of pneumonia.
Chest radiography is the essential tool for the diagnosis of pneumonia.However, a normal X-ray does not exclude the latter [21] [22], as reported in Central African Republic by Demers et al. [23], where only 41% of children had a pathological radiograph and 53% in South Africa According to Vérani et al. [24].In this work, 3.8% of children had a normal X-ray.It is here that the WHO criteria become important in resource-limited countries and/or there is a high morbidity Open Journal of Pediatrics and mortality associated with pneumonia because they allow pneumonia to be confirmed before radiological imaging, and therefore, to make an early diagnosis [10].When pneumonia has a radiological translation, it is dominated by alveolar syndrome [13] [24] [25] [26].
The prevalence of Streptococcus pneumoniae raises the problem of the efficacy of immunization coverage in Brazzaville, as 80.6% of the children in our series were immunized.Although it has not been possible to determine the serotypes of isolated pneumococci, these results should prompt the Expanded Program on Immunization to be vigilant or even conduct a seroprevalence survey.
The paradox described above is not new since Kuti et al. in the Gambia, before us, had reported a predominance of Streptococcus pneumoniae whereas the vaccination coverage in their case was of the order of 81.9% [5].
The disparity in the severity profile of pneumonia is explained by the vaccine status of the study subjects, their nutritional status, the existence or absence of HIV seropositivity or antibiotic self-medication [5] [6] [7] [32] [33].A not inconsiderable proportion of the children in our series had these favorable factors: 19.4% were not vaccinated against pneumococcus, 14.4% against Haemophilus influenzae b, 24.4% were emaciated or severely emaciated, and 8% Had HIV positive serology.
Regarding HIV infection, Oko et al. in Brazzaville, claim that pneumonia of the child of less than 12 months is one of the revealing modes of it [33].

4) Evolution
The mortality rate observed in our series (24%) is high.Demers [18] report lower rates.The factors cited upstream, justifying the severe forms of pneumonia can explain this heavy mortality.
In this study, 65.5% of children had died within the first 48 hours and the risk of death during this time was 2.9 times greater than that.Tiewsoh et al. in India [18] as well as Oko et al. [33] in Brazzaville had before us made the same observation.The sociodemographic determinants of pneumonia mortality are: the young age of the mother [RR = 2.9; CI 1.7 -4.9] and Unschooled [RR = 3.4; CI 1.7 -4.9], and the low socio-economic level of the family [RR = 1.8;IC 0.9 -3.4].In Gambia, Kuti et al. [6] report results similar to ours in terms of socio-economic level; In Brazil, De Fonseca Lima et al. [34], with regard the young age of the mother and her low level of education, which according to these authors put children twice as likely to die from pneumonia.In Brazil, Nascimento et al. explain these results by the immaturity of mothers and their unpreparedness to take care of a child [35].

5) Determinants and factors associated with mortality
WHO [36] reports that the infant and child mortality rate is 104 per thousand for low-income families, while families with a high socio-economic status have a mortality rate of 62 per thousand.Similarly, the mother's level of education has a direct influence on the infant mortality rate.A child whose mother has no education is 1.5 times more likely to die before the age of 5 than the mother whose education is at least secondary.Jroundi and Demers [19] [23] note no link between socio-demographic characteristics and death.
The protective role of exclusive breastfeeding already reported [37] [38], thus reinforces the WHO recommendation for the practice of exclusive breastfeeding for up to 6 months [36].
The environmental determinants of mortality are as in the works of Fakunlé, Cardoso and Shah [17] [38] [39]: the promiscuity and use of the oil lamp.
For promiscuity, the risk of mortality is high when the child shares the room with at least two other people.In India, Shah et al. [39] report that occupying a room by more than two people increases the risk of dying from pneumonia by 1.8 times.This result is not to be used for comparison in other studies.Indeed, the notion of promiscuity is to be relativized since it depends not only on the number of people who occupy a room but also on the dimensions of it and of what it contains.
Regarding the use of oil lamps in India, Sharma et al. report that they would increase the risk of mortality from pneumonia by 4.1 times [40].These authors explain that petroleum lamps are potential sources of particularly harmful substances such as polycyclic aromatic hydrocarbons, aliphatic hydrocarbons and hydrocarbon nitrates that are inhaled deeply into the lungs [41].
The risk factors for mortality identified are those described in the literature:

Table 2 .
Distribution of children according to living conditions.

Table 3 .
Signs of examination.

Table 4 .
Relationship between age and severity of pneumonia.

Table 5 .
Determinants of pneumonia mortality.

Table 6 .
Factors associated with pneumonia mortality.