Profile: Maternal and Child Health Surveillance System in peri-urban areas of Karachi, Pakistan

Key messages

•    The Karachi Maternal and Child Health Surveillance System (KMCHSS) is a large demographic health surveillance system with a population of 302,944 in low socioeconomic peri-urban settings in Pakistan.

•    It was designed as a platform to conduct epidemiological studies and provide a comprehensive sampling frame for these studies.

•    The current focus is on etiological studies and controlled trials in the field of maternal and child health.

•    All the studies aim for the improvement of public health policies and informed decision-making at local and national levels.

Why was the HDSS set up?

The world urban population is estimated to increase from 54% in 2014 to 66% (2.5 billion) by 2050 of which, about 90% is concentrated in developing countries¹ In Pakistan, Sindh is the most urbanized province where Karachi, a mega city, with the largest population is located. Urban dwellers mostly reside in settlements in peri-urban areas with the highest population density. These peri-urban areas experience a high maternal and childhood mortality^2,3. Additionally, Pakistan has a national database for registering vital events, such as births and deaths, but the coverage is sub-optimal with many births and deaths going unrecorded. Undercounting of these events leads to inaccurate estimates of vital health indicators. This inaccuracy hinders the setting up of priorities and allocation of scarce resources at the national level. Thus, the Karachi Maternal and Child Health Surveillance System (KMCHSS) was established in its rudimentary form in 2003 by the department of pediatrics and child health of the Aga Khan University, Pakistan, in peri-urban areas of Karachi, with the mandate and aim to provide a research platform for both observational and interventional studies that could influence decision-making and planning for health strategies at local, national and international levels, as well as research training opportunities for students in maternal and child health. At the outset, various epidemiological studies were conducted in the area on infectious diseases of children, vaccine coverage and the impact of multiple interventions to fill the gap by providing essential information on the key indicators through regular data collection.

Some of the initial studies included identifying signs and symptoms in young infants requiring urgent referral and measuring the incidence of vaccine-preventable diseases such as rotavirus associated diarrhea, pneumonia, invasive pneumococcal disease (IPD), typhoid bacteremia and diseases such as omphalitis and their contribution in causing neonatal mortality^4–7.

What does it cover now?

The KMCHSS is an efficient, cohesive, and dynamic surveillance system. It regularly collects information on vital and demographic events. Additional studies later included, studying etiology of moderate to severe diarrhea, the Global Enteric Multicenter Study (GEMS), comparison of effectiveness of different antibiotic regimens given as an outpatient therapy for management of sepsis in young infants, Simplified Antibiotic Therapy Trial (SATT) and a community-based etiology study of possible serious bacterial infections in young infants (0–59 days), Aetiology of Neonatal infection in South Asia (ANISA)^4–6. Currently, ongoing studies include, exploring coverage of routine childhood immunizations and their impact on disease transmission e.g., impact of 10 valent pneumococcal vaccine on nasopharyngeal carriage, a randomized control trial for comparison of Amoxicillin and placebo in non-severe pneumonia in children 2 to 59 months old (RETAPP) and usefulness of thermal images in diagnosing pneumonia in children under five years of age. In order to understand the intergenerational effects of disease across the continuum of adult female, maternal and child health, relevant large cohort studies were added, Alliance for Maternal and Newborn Health Improvement study (AMANHI)^7–12.

MCHSS structure

What area does it cover?

The KMCHSS is located in peri-urban areas of Karachi which is the largest metropolitan city, a commercial hub, and a principal port of Pakistan. Karachi has an estimated population of 23 million including peri-urban areas¹³. Located by the Arabian Sea, the KMCHSS was established in four peri-urban low-income communities in Korangi and Bin Qasim towns initially and extended to a fifth site recently. Of the four peri-urban communities, four are contiguously located along the seacoast of Karachi: Ibrahim Hyderi, Ibrahim Hyderi extension, Ali Akbar Shah Goth, and Rehri Goth. The KMCHSS lies on the latitude 24.8508° N and longitude 67.0181° and covers an area of 17.7 km² (Figure 1). Fishing is the main occupation of people living in these communities. The fifth community, Bhains colony, is located at the outskirts of Karachi and the source of their livelihood is cattle rearing. In recent years, Bhains colony has shown rapid urbanization.

Figure 1. Map showing location of the Demographic Surveillance System sites in Pakistan, Karachi, and Bin Qasim town.

In 2010, the area was digitally mapped using global positioning system (GPS) techniques and boundaries were constructed. The area is divided into 238 blocks each comprising of 200–250 structures. There are 42,565 structures in which 50,245 households are living. Each site has its own primary health care (PHC) center that has been established and operated by the Aga Khan University department of pediatrics and child health. These PHCs are accessible to populations within their catchment area and provide free care to children under five years of age.

Who is covered by the KMCHSS and how often have they been followed up?

The KMCHSS currently covers all the residents in the defined catchment areas with a particular focus on married women of reproductive age and their children under five years of age. In this system we define a ‘structure’ as a building with a single entrance and a boundary. These structures can be houses, hospitals, dispensaries, schools, shops, parks etc. Each structure has a nine-character unique number assigned to it which is written on the front door of each structure with black permanent paint to withstand the weather changes. A ‘household’ is a group of people living together under a roof (structure) and sharing the same cooking pot using the as per the International Network for Demographic Evaluation of Populations and Their Health (INDEPTH) definition of household¹⁴. As the household is a basic unit, thus the number of households in each structure are determined, enumerated using an 11-character unique identification number. A ‘resident’ is defined as a person who stayed for at least six months or intends to stay for more than six months in the community¹⁵. The KMCHSS was established stepwise. It was initiated in 2003 in four peri-urban areas with focus on providing a platform to various studies. In 2010, the area was geo-mapped, and the first census was conducted. In 2014, it was extended to an additional area where the census was conducted in 2014. The most recent census was conducted in 2017. Until 2014, quarterly enumeration was done, and since then it has intensified to every two months, to be done by trained community health care workers (CHWs). They captured all new pregnancies, births, deaths and in and out migrations. CHWs are females with a secondary level of education and are mostly residents of the same communities where the surveillance is taking place.

We conducted a census by the end of 2017. The KMCHSS has a current population of 302,944 with 155,622 (51%) males and 147,322 (49%) females. Of the total population, 25% are females of reproductive age (between 15 to 49 years) and 14% are children under five years of age. The population age and sex structure are given in Figure 2.

Figure 2. Population age and sex structure in 2017.

Database

The data was entered and stored in a relational database with event-based programming developed using Microsoft Access 2010. A series of data quality checks were in-built to identify the inconsistencies and errors in data collection. It consisted of data entry screens, data edit and update screens, customized reports generation and data cleaning modules. A backup was also created. Routine error reports were generated during the round and at the end of surveillance round and discussed with the site supervisor and coordinators by the data manager. All data queries were resolved before the end of a surveillance round. Clean data was encrypted and archived in a server at the Aga Khan University, Karachi Pakistan.

With the availability of newer technology, we had a transition from paper-based data collection to data collection on tablets/smartphones in 2017. Android mobile apps are developed for remote data collection. The data is stored in coded values in MySQL database hosted on a local machine inside Aga Khan University. All the data is synchronized and updated on the server daily.

Key findings and publications

The main demographic indicators across a period of six years have been represented in Table 2. There has been a decline in overall mortality rates. In the year 2017, these sites had a Crude birth rate (CBR) of 28.8, maternal mortality ratio (MMR) of 252 per 100,000 live births, neonatal mortality rate (NMR) of 42.6, Infant mortality rate (IMR) of 60.1 and under-five mortality (U5MR) of 69.5 per 1000 live births and stillbirth rate (SBR) of 32.4 per 1000 births. We recorded more in-migrations than out-migration at the surveillance sites (Table 2).

Figure 3 describes the trends in child mortality from 2012 to 2017. Under-5 mortality rates (U5MR) peaked in 2013 and 2016 due to the measles epidemic. Within the time period of six years, a reduction in neonatal mortality rates was observed. (Table 2 and Figure 3).

Figure 3. Child Mortality Rates from 2012–2017, U5MR, under-five mortality rate; IMR, infant mortality rate; NMR, neonatal mortality rate.

Several studies conducted in the KMCHSS have led the efforts to aid policy makers in making important decisions. One of these studies was the young infant clinical signs study (YICSS), which led to the formulation of WHO seven sign algorithm for detection of possible serious bacterial infection (PSBI) in young infants. This algorithm was then incorporated into the Integrated Management of Childhood Illness (IMCI) and is in use to date²¹. A randomized control trial (RCT) compared procaine-penicillin and gentamicin, ceftriaxone and trimethoprim-sulfamethoxazole (TMP-SMX) regimens for the treatment of newborns, aged 0 to 59 days, with PSBI in an outpatient setting when hospitalization is declined. TMP-SMX showed the highest failure rate and case fatalities. Procaine penicillin-gentamicin turned out to be the most cost-effective route to treat these bacterial infections⁷. As a follow up to this trial, a randomized control open-label equivalence trial (SATT) in young infants with clinically diagnosed severe infections (CSI), seen at PHC, was done. The trial aimed to evaluate if (1) IM gentamicin once daily (OD) and oral amoxicillin twice daily (BD) for 7 days; and (2) IM penicillin and gentamicin OD for two days followed by oral amoxicillin BD for five days are equivalent to seven days of (3) IM procaine penicillin and gentamicin (reference therapy). The primary outcome of this trial was treatment failure (death, deterioration, or lack of improvement) within seven days of enrollment. Treatment failure rate were equivalent across three regimens. These findings were subsequently incorporated in the WHO guidelines for the management of young infants with CSI, and IM gentamicin OD and oral amoxicillin BD for 7 days was chosen as the treatment of choice⁵. A study, Global Enteric Multicenter Study (GEMS), exploring etiology of moderate to severe diarrhea (MSD), using quantitative molecular diagnostic methods showed Shigella spp, Rotavirus, Adenovirus 40/41, ST-ETEC, Cryptosporidium spp, and Campylobacter spp are responsible for 77.8% of all diarrheal causes⁴. In another study, health seeking behavior for sick young infants was studied. The acceptance rate of hospitalized care was found to be 24%. Reasons for high refusal rate included financial difficulties, elders denying permission, and some based their decisions on religious and cultural beliefs. The acceptance of hospitalization was higher when the mother recognized the severity of the illness, presence of grunting, temperature <35.5°C and absence of language barrier at the local hospital. Gender was not a determining factor in decision making. This information forms learning points for interventions promoting health seeking behavior and formulation of alternative community based management plans for the betterment of child survival⁸. An RCT aimed to compare immunization coverage by administering pictorial messages promoting vaccines to mothers versus administering general health promotion messages to the control group. An improvement of 39% in the completion of DPT-3/Hepatitis B vaccines, which shows that simple health awareness interventions can go a long way in raising the health status of low-income communities⁸.

A randomized double blinded placebo-controlled equivalence trial was conducted in primary care settings, which aimed to determine optimal management of isolated fast breathing in young infants. The primary objective of the study was to evaluate if out-patient therapy of seven days of oral amoxicillin (reference therapy) is equivalent to the placebo. The primary outcome was to see the treatment failure by evaluation of hypoxia, organ failure, anaphylaxis, or hospitalization after treatment initiation. Amoxicillin treatment regimen was found to be more effective than placebo with risk difference of 3.1, p=0.04 (95% CI 0.3, 5.8)²². A cohort study on calculating the neonatal mortality within 24 hours of birth was conducted in the rural areas of six countries, including the KHDSS in Pakistan. The neonatal mortality rates were higher than the published model-based estimates for these countries. Around one third of the deaths occurred during first six hours after birth and a little under half of all neonatal deaths within 24 hours. The study concluded that implementing high quality obstetric and newborn care is a priority for preventing newborn deaths early on²³.

A randomized control trial (RCT) was conducted to see the immunogenicity of poliovirus vaccines in chronically malnourished infants. Infants were randomized to receive one dose of either bivalent oral poliovirus vaccine (bOPV) alone or in combination with inactivated poliovirus vaccine (IPV). The results showed that those who were given bOPV+IPV together showed to close the immunity gap more than those who were given bOPV alone²⁴.

A prospective cohort study in community-based research sites in south Asia and sub-Saharan Africa, between July 2012, and February 2016, we conducted population-based surveillance of women of reproductive age (15–49 years) to identify pregnancies, which were followed up to birth and 42 days post-partum. Verbal autopsies were done for deaths of all women of reproductive age, neonatal deaths, and stillbirths. Physicians used standardized methods for cause of death assignment¹⁰. This study revealed maternal mortality ratio (MMR) of 460 per 100000 live births, stillbirth rate (SBR) of 37.8 per 1000 births and neonatal mortality rate (NMR) of 50.1 per 1000 live birth. On VA analysis, among maternal deaths obstetric hemorrhage and hypertensive disorders in pregnancy contributed most to pregnancy related deaths, while neonatal deaths among perinatal asphyxia, sever neonatal infections and preterm birth complication and among stillbirths maternal infections, hypertensive disorders and antepartum hemorrhage were major causes of deaths³.

Future analysis plans

Future analysis plans include analysis of data from the multi-center Aetiology of Neonatal infection in South Asia (ANISA) study⁶. We are also conducting analysis to determine the burden of major maternal morbidities as part of the AMANHI study¹¹. An additional analysis is on simplified methods to determine gestational age at birth by using a combination of physical and neurodevelopmental parameters. Also, as a part of AMANHI, we have established a biorepository of maternal, newborn, and paternal samples, collected at various time points during and after pregnancy. To the best of our knowledge, this is the only population-based biobank in Pakistan and one of the few in the region. Recently, we have secured funding from the Bill & Melinda Gates Foundation to follow the AMANHI bio-bank cohort for up to three years for neurodevelopmental milestones.

Strengths and weaknesses

In our demographic and surveillance system, all inhabited and uninhabited structures in the area have been mapped and surveyed. Each individual has been assigned a unique ID and surveyed every two months. The GIS coordinates of these structures, allow us to look at the spatial distribution of various maternal and newborn health indicators. Active surveillance of maternal and child health allows for the cohort to be a part of many multicenter studies, conducted with multiple international collaborators. Our long-term presence in the area has helped us establish good rapport with the population resulting in very low refusal rates.

Currently, the KMCHSS focuses on children under the age of five years and women of reproductive age, however the vital status and migration status of all household members are recorded. In the future, given adequate amount of funding we would like to expand our surveillance to cover these populations as well. With transition to electronic data collection and monitoring, we are aiming to integrate the surveillance system with our health center for electronic health records for better services to the community

Conclusions

All the studies conducted at our surveillance sites aim for improvement of public health policies. The information we derive, aid us in making informed decisions at local, national, and international levels. These sites also play vital roles in training research personnel.

Ethical statement

Ethical approval for individual studies is obtained from Aga Khan University’s Ethical review committee. Written informed consent for publication of the participants’ details was obtained from the participants/parents/guardian/relative of the participant.