Serologic Evidence of Measles IgM Antibodies among Children in Two IDP Camps in Kaduna

attack (39.4%). From the questionnaires Major risk factors for the spread of measles in administered, all the participants were exposed displaced populations are: poor vaccination to crowd, all the mothers were illiterates and coverage, mass migration causing international farming was their major occupation. Inadequate spread of diseases and high density of refugee vaccination, malnutrition and lack of awareness population in the camps . The aim of this study are thought to be the reason for the high IgM was to determine the serologic evidence of antibodies. Measles awareness, and high measles IgM antibodies among children in two vaccination coverage in IDP camps is advocated. IDP camps (Ungwan zawu and Hayin Nariya) situated in Kaduna South and Kaduna North.

communal accommodation of evacuated or separated into cryo tubes and stored at -20 C. The displaced persons. IDP camps can be planned for frozen sera were thawed at room temperature for example purposely-built sites that is completed 45 minutes and screened for measles IgM before or during influx or can be self-settled, that antibodies using ELISA technique (EuroImmun is, set up spontaneously by internally displaced Medizinische Labordiagnostika AG, Germany) persons or host communities without the support according to manufacturer's instructions.
of the government or the humanitarian community Measles specific IgM antibodies was detected in (Kampala Convention, 2009). The United Nations 66 (34.4%) of the total 192 children in the two High Commissioner for Refugees (UNHCR) IDP camps studied. Males recorded higher states that as at April 2021 there have been an percentage prevalence of 63.6% compared to increased number of refugees and IDPs to 2.8 females (36.4%). Measles IgM antibodies varied million owing to internal conflicts and natural among the age grades, from 63.6% in children disasters (UNHCR, 2021). The health care aged >5years to 3.0% in children aged <1year. systems in these situations are often in a collapsed IDP Camp participants in Hayin Nariya camp state or may become non-functional. Also, recorded the highest measles IgM seropositivity inadequate vaccination coverage, high of 75.8% than those residing in Ungwan Zawu concentration of displaced settlers and (24.2%). Higher measles IgM antibody (51.5%) overcrowding in these camps are the ultimate was found among participants with no history of causes of increased risk of infectious disease such previous vaccination (51.5%) compared to as measles spread (Gayer et al., 2007). participants with history of vaccination (48.5%). Participants with previous history of measles Measles is a highly infectious disease caused by a attack recorded higher measles IgM antibodies (60.6%) than those without previous measles paramyxo-virus belonging to the genus Morbillivirus (Guerra et al., 2017). Symptoms of Salama, 2003;Gayer et al., 2007). Measles is a known measles disease include fever, cough, catarrh, cause of high morbidity and mortality mostly in inflammation of the conjunctiva and a generalized children, especially in developing countries resulting flat and raised, reddened erythematous rash in more than 95% measles-associated deaths (Bosan (Biesbroeck and Sidbury, 2013). The virus route et al., 2002;Mohan et al., 2005). Measles is a public of transmission is the respiratory tract by aerosol health concern among displaced persons owing to spread or contact with fluids by either droplet from their characteristic massive population displacement, infected person's nose and mouth (WHO, 2014).
high level malnutrition, overcrowding in camps and The virus is known to cause disease only in inadequate measles vaccination coverage among the humans and is highly contagious. Measles causes children (Kamugisha et al., 2003). The case fatality immunosuppression that persists for weeks to rates in stable populations is approximately 2% but months after the acute infection. This may usually higher among populations displaced by predispose infected individuals to severe bacterial disasters or other factors (Kouadio et al., 2010). There infections (Coetzee, 2013 the participating children before collecting their Despite the great efforts, measles elimination could samples. A well-structured questionnaire was not be achieved especially in developing countries also administered to collect bio-data, sociowhere there is massive population displacement.
demographic information and medical history of High measles associated death rates have been each participant. recorded in IDP camps as a major cause of child deaths in humanitarian emergencies (Tailey and

Sample Collection and Analysis
between 620nm and 650nm within 30 minutes of Venipuncture method of blood collection was adding the stop solution. used to obtain about four (4) milliliters of blood from the children using disposable syringe and Results Interpretation needles. After collection, the samples were The extinction value of the calibrator defines the dispensed into sterile plain containers, allowed upper limit of the reference range of non-infected to clot, spun at 3,000rpm for 10minutes and the p e r s o n s ( c u t o f f ) r e c o m m e n d e d b y resultant serum was separated into cryo tubes EUROIMMUN. Values above the indicated cut 0 off are to be considered as positive while those and stored at -20 C. The frozen sera were below as negative. allowed to thaw at room temperature for about 45 minutes. The thawed sera were each screened for Semiquantitative: Results can be evaluated semi measles IgM antibodies using Enzyme Linked quantitatively by calculating a ratio of the Immunosorbent Assay (ELISA) technique extinction value of the control or patient sample (EuroImmun Medizinische Labordiagnostika over the extinction value of the calibrator. The AG, Germany).
following formula was used to calculate the ratio: Extinction of the control or patient sample: Each patient sample was analyzed according to Extinction of calibrator manufacturer's instructions. Briefly, each patient EUROIMMUN recommends interpreting sample was diluted 1:101 with sample buffer; that results as follows: Ratio <0.8: negative; Ratio is 10ul sample to 1.0ml sample buffer, mixed well >0.8 to <1.1: borderline and Ratio >1.1: positive and incubated the mixture for at least 10min at room temperature. About 100ul of the calibrator, Statistical Analysis positive and negative controls and each diluted The descriptive statistics obtained from patient samples were transferred into the laboratory investigations was tabulated, encoded individual microplate wells according to the and statistically analyzed using Statistical pipetting protocol and incubated for 30 minutes at 0 Package for Social Sciences (SPSS) program. room temperature (25 C). The reagent wells were Chi square levels of significance were accepted washed 3 times with 450ul working strength wash at p<0.05. buffer. The wash buffer was left in each well for 30 to 60 seconds per washing cycle and emptied Results afterwards. After washing, the liquid was Measles specific IgM antibodies by ELISA was thoroughly disposed from the microplate by detected in 66 (34.4%) of the total 192 children in tapping it on absorbent paper with the openings the two IDP camps studied (Table 1). Males facing downwards to remove all residual wash recorded higher percentage prevalence of 63.6% buffers. One hundred microliter (100ul) of to females 36.4%. This was statistically enzyme conjugate (peroxidase labelled anti significant (P=0.023, OR=2.052, 95% human IgM) was pipetted into each of the CI=1.110-3.782) ( Table 2). microplate wells. The preparation was incubated for 30 minutes at room temperature (Conjugation).
Measles IgM antibodies varied among the age The wells were emptied and washed. Thereafter, grades, from 63.6% in children aged >5years to 100ul of chromogen/ substrate solution was 18.2% in children aged 3-4years to 15.2% in pipetted into each of the microplate. It was children aged 1-2years and 3.0% in children incubated for 15 minutes at room temperature, aged <1year (Table 2). Age grade significantly protected from direct sunlight (Substrate influenced the incidence of measles incubation). Subsequently, 100ul of stop solution seropositivity among our study participants (Pwas pipetted into each of the microplate wells in 0.004, OR -0.274, 95% CI -0.06-1.36). the same order and at the same speed as the chromogen/substrate solution was introduced IDP Camp participants in Hayin Nariya camp (Stopping the reaction). Photometric recorded the highest measles IgM seropositivity measurement of the color intensity was made at a of 75.8% when compared with their counterparts wavelength of 450nm and a reference wavelength residing in Ungwan Zawu which recorded 24.2%.
Measles IgM antibody seropositivity was higher From the questionnaires administered, based on among participants that had no history of exposure to crowd as one of the risk factors for previous vaccination (51.5%) when compared to acquiring measles, all the children studied in the participants that had history of previous two IDP camps were exposed to crowd. All the vaccination (48.5%). Among the 48 cases that mothers were illiterates and farming was their had previous history of measles attack, 60.6% major occupation. were measles IgM antibodies seropositive while     (Wolfson ., 2009). Similar to our study, a total of 47,173 cases of suspected seropositivity of 75.8% when compared with measles infected children were screened in some their counterparts residing in Ungwan Zawu parts of Nigeria between January and July 2013 (24.2%). Crowded and clustered conditions of and a total of 34, 963 tested positive for measles the settlement pattern of the houses and settlers IgM antibodies (CDC, 2013).
in the Hayin Nariya camp might be the reason for this higher IgM antibody. Higher measles IgM Our study recorded a significantly higher antibody seropositivity (51.5%) was found percentage of males having measles IgM among participants that had no history of antibodies than females. Similarly, a study on previous measles vaccination while 48.5%