Survey of poliovirus antibodies in Borno and Yobe States, North-Eastern Nigeria.

BACKGROUND: Nigeria remains one of only three polio-endemic countries in the world. In 2016, after an absence of 2 years, wild poliovirus serotype 1 was again detected in North-Eastern Nigeria. To better guide programmatic action, we assessed the immunity status of infants and children in Borno and Yobe states, and evaluated the impact of recently introduced inactivated poliovirus vaccine (IPV) on antibody seroprevalence. METHODS AND FINDINGS: We conducted a facility-based study of seroprevalence to poliovirus serotypes 1, 2 and 3 among health-seeking patients in two sites each of Borno and Yobe States. Enrolment was conducted amongst children 6-9 and 36-47 months of age attending the paediatrics outpatient department of the selected hospitals in the two states between 11 January and 5 February 2016. Detailed demographic and immunization history of the child was taken and an assessment of the child's health and nutritional state was conducted via physical examination. Blood was collected to test for levels of neutralizing antibody titres against the three poliovirus serotypes. The seroprevalence in the two age groups, potential determinants of seropositivity and the impact of one dose of IPV on humoral immunity were assessed. A total of 583 subjects were enrolled and provided sufficient quantities of serum for testing. Among 6-9-month-old infants, the seroprevalence was 81% (74-87%), 86% (79-91%), and 72% (65-79%) in Borno State, and 75% (67-81%), 74% (66-81%) and 69% (61-76%) in Yobe States, for serotypes-1, 2 and 3, respectively. Among children aged 36-47 months, the seroprevalence was >90% in both states for all three serotypes, with the exception of type 3 seroprevalence in Borno [87% (80-91%)]. Median reciprocal anti-polio neutralizing antibody titers were consistently >900 for serotypes 1 and 2 across age groups and states; with lower estimates for serotype 3, particularly in Borno. IPV received in routine immunization was found to be a significant determinant of seropositivity and anti-polio neutralizing antibodies among 6-9-month-old infants for serotypes 1 and 3, but demonstrated a non-significant positive association for serotype 2. Children receiving IPV through SIAs demonstrated significantly higher anti-polio neutralizing antibodies for serotypes 1 and 3. CONCLUSIONS: The seroprevalence to poliovirus remains suboptimal in both Borno and Yobe States in Nigeria. The low seroprevalence facilitated the continued transmission of both wild serotype 1 and serotype 2 circulating vaccine-derived poliovirus detected in Borno State in 2016. Further efforts are necessary to improve the immunity status of these populations to ensure sufficient population immunity to interrupt transmission.

Neonatal Tetanus Immunity in Nigeria: The Effect of HIV Infection on Serum Levels and Transplacental Transfer of Antibodies.

Background. Tetanus toxoid immunisation of pregnant mother has remained the most effective strategy in eliminating neonatal tetanus. Impaired production and/or transplacental transfer of antibodies may affect the effectiveness of this strategy. We studied the effect of maternal HIV infection on serum levels and transplacental transfer of anti-tetanus antibodies. Methods. A total of 162 mother-baby paired serum samples were taken and analysed for anti-tetanus antibody levels using ELISA. Maternal HIV status was also determined by double ELISA technique. Maternal TT vaccination status was also documented. Results. Thirty-eight (23.5%) mothers and 41 (25.3%) babies were seronegative, out of whom 8 mothers were HIV positive and 9 babies were HIV exposed. HIV infected mothers and HIV exposed infants were, respectively, 16.27 times (OR = 16.27, 95% CI = 3.28 to 80.61) and 33.75 times (OR = 33.75, 95% CI = 4.12 to 276.40) more likely to be seronegative for anti-tetanus antibody. Similarly, HIV positive mother-newborn pairs were 7.46 times more likely to have a poor transplacental transfer of tetanus antibodies (OR = 7.46, 95% CI = 1.96 to 28.41). Conclusions. Maternal HIV infection is associated with impaired maternofoetal transfer of anti-tetanus antibodies and seronegativity among mothers and their newborns. Hence, this may hinder efforts to eliminate neonatal tetanus.

Uncomplicated malaria in children: The place of rapid diagnostic test.

BACKGROUND: Malaria has remained a major cause of morbidity and mortality among the under-five children in Nigeria. Prompt and accurate diagnosis of malaria is necessary in controlling this high burden and preventing unnecessary use of anti-malarial drugs. Malaria rapid diagnostic test (MRDT) offers the hope of achieving this goal. However, the performance of these kits among the most vulnerable age group to malaria is inadequate. MATERIALS AND METHODS: In this cross-sectional study, 433 out-patients, aged <5 years with fever or history of fever were enrolled. Each candidate was tested for malaria parasitaemia using ACON; malaria pf. Thick and thin films were also prepared from the same finger prick blood for each candidate. RESULT: Malaria rapid diagnostic test had sensitivity of 8.3%, specificity of 100%, positive predictive value (PPV) of 100% and negative predictive value (NPV) of 74%. The sensitivity of MRDT increased with increasing age. This effect of age on sensitivity was statistically significant (P = 0.007). Similarly parasite density had significant effect on the sensitivity of MRDT (P = <0.001). CONCLUSION: Histidine-rich protein-2 based MRDT is not a reliable mean of diagnosing malaria in the under-five age children with acute uncomplicated malaria.

A sero-survey to identify the window of vulnerability to measles in infants in North-Eastern Nigeria

As infants lose maternal measles antibodies (MMAs); they experience periods when their antibody levels are insufficient to protect them against measles. A prospective study was carried out at the University of Maiduguri Teaching Hospital. Sera collected from neonates at birth; and at six weeks; three months; six months and nine months of age; were analysed for MMAs by enzyme-linked immunosorbent assay. Seventy-seven neonates were enrolled. Of these; 73 (94.8) had protective MMAs at birth. This figure declined to 36 (46.8); 28 (36.4); 13 (16.9) and 4 (5.2) at six weeks; three months; six months and nine months of age (?2 = 154.264; p-value = 0.000). Protective MMAs at birth waned rapidly; resulting in an early window of vulnerability to measles by the age of six months. Protecting infants with early measles immunisation with potent; safe vaccines are recommended

Tetanus following tongue bite from repeated convulsions: a case report.

This report details a case of generalized tetanus with the added complication of tongue bite following the repeated convulsions of a six-year-old unimmunized girl. It highlights the fact that tongue bite is an unusual portal of the entry of tetanus and emphasizes the need for proper oral care of an unconscious patient and the importance of the immunization of children.

Mantoux test reactions among children managed for tuberculosis in Maiduguri, Nigeria.

Abstract We conducted a study of Mantoux reactions in children managed for tuberculosis (TB) at the University of Maiduguri Teaching Hospital (UMTH) over a period of 4 y. Of the 97 eligible children managed for various forms of TB on whom a Mantoux test was conducted, 82 (84.5%) had a negative Mantoux reaction and 15 (15.5%) had a positive reaction. No statistically significant difference was found in relation to age groups and sex between the patients with positive and negative Mantoux reactions (p = 0.602 and p = 0.484, respectively). No significant difference in Mantoux reaction was observed among BCG-vaccinated and non-vaccinated children (p = 0.321). Although malnutrition and HIV infection were significantly associated with a negative Mantoux reaction, disseminated TB was not associated. We therefore recommend proper clinical assessment and other investigations for the diagnosis of TB in children in settings with a high prevalence of HIV infection and malnutrition, as Mantoux reaction results may be unreliable.