Background
Malaria is the most common vector-borne infectious disease of tropical and subtropical regions [
1]. In India, Madhya Pradesh (M.P.) is the fourth most malaria endemic state, contributing about 7 % of total malaria cases [
2]. Vector control is an important component of malaria control programmes, and it includes Indoor Residual Spraying (IRS) and the use of Long-Lasting Insecticidal Nets (LLINs) [
3]. During the early 20th century, IRS was the key malaria control intervention achieving spectacular reduction in malaria [
4‐
6]. In IRS, the insecticide is sprayed on the walls of houses and as a result when mosquitoes rest on these sprayed walls, they pick up the particles of insecticide, and lose their longevity [
7]. The same concept applies in LLINs, and in addition, the nets prevent human to mosquito contact.
The World Health Organization (WHO) and Roll Back Malaria Partnership to End Malaria (RBM) have prepared materials and strategies for a malaria-free world by 2030 [
8]. SEAR countries identified 2030 as a target for malaria free Asia Pacific. The Indian Government along with other Governments of Asia Pacific countries have committed to this target [
9]. National Vector Borne Disease Control Programme (NVBDCP) has launched a national framework to eliminate malaria by 2030 [
10]. The Operational Guidelines for Implementation of Malaria Programme 2009 by NVBDCP are followed by the Government of MP [
11].
As per the national guidelines, the Government of Madhya Pradesh (GoMP) uses IRS in sub-centres which score 2 to 4.99 on the Annual Parasite Incidence (API). In Mandla, as per Memorandum of Understanding between the Government of MP, Indian Council for Medical Research (ICMR), and Foundation for Disease Control and Elimination of India (FDEC India), this criteria for IRS was revised to 1 to 4.99 to cover more sub-centres. The alpha-cypermethrin (ACM) 5 % insecticide (synthetic pyrethroids) was sprayed with the help of 18 squads consisting of one senior field worker (SFW) and 5 field workers (FW) with two pumps in each squad.
LLIN is a long-term anti-mosquitoes measure with effects lasting for 3–5 years [
12]. A meta-analysis of the efficacy of insecticide-treated bed nets in 29 countries of sub-Saharan Africa showed a pooled reduction by 24 % in parasitaemia prevalence in children and 23 % reduction in under five child mortality rates over the last decade [
13]. This vector control strategy is also endorsed by the WHO as one of the strategies for controlling and preventing human-to-mosquito contact [
12].
Methods
Study area
The study was carried out in Mandla district of Madhya Pradesh, which is located in the south-eastern part of the state as part of the Malaria Elimination Demonstration Project [
14]. The area is covered with dense forests, valleys and mountains (23° N latitude, 80° 10’ E longitude). The total district area is 8771 km
2 and is home to approximately 1.15 million population [
15] with about 90 % population living in the rural areas. Mandla experiences summers from March to June, monsoons from July to October, and winters from November to February.
Study design, training, sampling technique and sample size
In this study, training and supervisory support was provided for both IRS and LLIN campaigns. In the year 2017, IRS was monitored for both rounds consisting of 45 days each. Based upon the findings of 2017, in the year 2018, the supportive supervision of spraying teams along with post-distribution monitoring of usage of LLINs was performed. Based upon the findings of 2018, in the year 2019, supportive supervision for distribution of the LLINs was provided and their usage was observed in 2020.
One-day training was provided to each team on the do’s and don’ts about the IRS and LLINs. The training regimens included components on preparedness, operations, safety measures and evaluation. The spraying team was advised to follow: (1) date-wise route chart; (2) record the number of rooms, houses sprayed, locked or refused in the register; (3) record attendance of the team members; (4) maintain stock register for entry of spray pumps, nozzles, and solution; and (5) maintain the daily diary. Proper training for maintenance of the records was given before IRS programme each year.
During the spray operations, the spray team and supervisor were advised to: (1) check the spray equipment for proper discharge rate; (2) solution preparation; (3) correct mixing; (4) spray technique; and (5) usage of proper safety equipment. They were also trained for post-spray activities i.e. (1) washing of spray equipment; (2) disposal of leftover solution; (3) coverage of rooms; and (4) observation of any side effects. For LLIN distribution and evaluation, the staff was trained to: (1) perform household survey to determine number of required nets; (2) verify distributed vs. required nets; (3) assess proper usage of nets; (4) assess washing practices; and (5) observe any side effects because of usage of nets.
The IRS campaigns were observed during 45 days for each round of spraying (16th June to 31st July and 1st September to 15th October 2017) using a pre-tested, closed-ended monitoring checklist. The checklist consisted of two parts: (1) observations of spraying team; and (2) observations of sprayed houses. Each spraying team used an advance tour plan for spraying of households. The teams were intercepted in their target villages on different days and the questionnaire tool was administered. Each spraying team was monitored using the checklist for 159 times in 2017 and 183 times in 2018. The project staff supervised the IRS operations in 2018. For observing the sprayed houses, one checklist was administered in randomly selected sprayed households yielding a total sample size of 1261 and 1791 in the years 2017 and 2018, respectively.
While the WHO universal coverage proposes use of one LLIN per 1.8 individuals [
13]. The NVBDCP has recommended one LLIN should be distributed per 2.5 individuals [
16]. Accordingly, the State of MP used NVBDCP recommendation of one net per 2.5 individual. During this study, the use of LLINs was assessed periodically to determine proper usage that interrupts human mosquito contacts. In this study, usage of 4,879 LLINs was checked in about 2000 (5 %) households in 2019 for the nets distributed in 2018. In 2019, MEDP provided supportive supervision to the state government in distribution of next batch of LLINs and checked usage of 4,967 LLINs in about same number of households in 2020.
Data management and analysis
The data was entered in data entry software designed on CS-Pro 7.0 platform and data analysis was done with Statistical Package for Social Sciences (SPSS) v20.0 by IBM.
Discussion
There was significant improvement in the outcome of IRS as a result of supportive supervision between 2017 and 2018. In the year 2017, between the spraying dates of 16th June to 31st August and 16th September to 30th October, a total of 301 malaria cases were detected in the district, whereas, within the same dates in the year 2018, only 43 malaria cases were found. This significant drop may be attributed in-part due to the improvement in spraying quality during 2018. Additionally, entomological investigations as part of this project [
17] has revealed 41 % mortality of
Anopheles culicifacies on 30-day post-spraying in July 2017 and 61.3 % in July 2018. This can also be attributed to the improved quality of spraying in 2018. However, there was a reduced mortality (44.4 %) of
An. culicifacies in October 2018 [
17] which suggests the need for stringent training, monitoring, and supervision during IRS campaigns [
18].
It was noticed that spraying teams behave and operate much more efficiently in the presence of a supervisor. The art of spraying which involves movement of hands in defined direction and particular order is critical for the success of IRS campaigns. Therefore, the business-as-usual practice by spraying teams that are not provided routine trainings and are not subjected to in-person supervision most likely results in ineffective spraying. These observations inform us that the spraying teams should have full-time supervision and be regularly trained so that investments in IRS produce the desired result.
An earlier study conducted in district Betul of Madhya Pradesh, malaria was controlled by using IRS along with other intervention during the year 2001 to 2005. In this study, the slide positivity rate (SPR) in pre-intervention stage was > 47 % which declined gradually to 1.3 % [
19]. Another key observation from this study was that the vector density also declined significantly after intervention [
19]. The present study has revealed about 91 % reduction of indigenous cases of malaria during the period from June 2017 to May 2020, through case management and vector control strategies [
20]. Another study of malaria control was conducted in the
Baigachak area of Dindori district of Madhya Pradesh, where a remarkable 89 % reduction in malaria prevalence was achieved in the year 2013-14 using combined intervention measures IRS, LLINs, prompt diagnosis and treatment along with intensive Information, Education and Communication (IEC) [
21].
IRS and LLINs are effective for limiting malaria transmission [
3]. The results from randomized comparisons of IRS
versus no IRS revealed that IRS reduces malaria incidence in unstable malaria settings [
22]. Similar findings were found in Equatorial Guinea and Western Kenya [
23,
24]. Similarly, malaria control programmes in Europe, Asia and the Americas that have resulted in saving hundreds of millions of lives between the 1940s and the 1980s, benefitted by IRS as a vector-control intervention [
25].
Based on the findings, it is suggested that IRS operations, while they may seem simple, but in practice, requires management by skilled professional staff. The supervisor as well as the spraying team has to understand local epidemiology, transmission dynamics, vector behaviour and insecticide resistance status [
26]. It is worth noting that similar observations were also made in a study of IRS usage in Visceral Leishmaniasis control [
27].
In the LLIN component of the present study, the average acceptance of use of LLINs was observed 91 %. These findings are different from an assessment study done in the Buie and Fentalie districts of Ethiopia, where the rate of retention of bed nets was 72 %, and 60.5 %, respectively. The reason for difference of Ethiopian study with our study towards acceptance or retention may be due to the fact that our assessment was done after six to eight months of distribution of LLINs, whereas, in Ethiopia the difference between distribution and assessment was three years. In the same study, majority of people knew that the nets were for protection against mosquito bites (82.4 %) and malaria (14.3 %) [
28], which is similar to the findings of the present study where 99.4 % were aware about the purpose of bed nets.
There was also an increase in number nets being used regularly by the residents in 2019-20 as compared to 2017–2018. This increase in usage of beds nets can be attributed to awareness campaigns that informed the villagers about benefits of bed nets as well as their proper use. During the distribution in 2019, MEDP stationed its staff at each LLIN distribution site in the district and facilitated the process along with live demonstrations and IEC/BCC messages to each recipient. This helped in increasing usage of LLINs, acceptance of adverse effects, and increase in usage of nets while traveling outside homes.
Additionally, using supportive supervision, strict monitoring was done to ensure fair distribution practices, which has yielded a near zero complaints of money charged for LLIN distribution (0.2 %) as compared to 2017 (3.8 %). In 2019-2020, lesser number of people reported spending nights outside their homes. This may be due to the peak winters at the time of the survey. However, more people took LLINs with them for spending nights as compared to the 2017 survey. This improvement can be attributed to regular inter-personal communication conducted by MEDP during regular field visits to these villagers.
A systematic review of the Cochrane database to compare ITN vs. curtains or no bed-nets, has revealed that ITNs provide 17 % more efficacy compared to no nets, which results in 5.5 lives saved each year for every 1000 children protected with ITNs. In areas of stable malaria, ITNs reduced the incidence of uncomplicated malaria by 50 % and in unstable areas by 62 % when compared to no nets. ITNs also had impact on severe malaria, parasite prevalence, high parasitaemia, splenomegaly and also improved average haemoglobin level in children by 1.7 % packed cell volume [
29].
An evaluation of LLIN distribution in Togo, West Africa, was done, where 93.4 % respondents received visits and awareness messages from a community health worker [
30]. In the present study, almost none of the respondents received any awareness drives by the health worker on proper usage of these nets in 2017. Therefore, awareness campaigns should be conducted during distribution of LLINs in addition, strict monitoring and follow-up after distribution of LLINs should be built-in as a practice.
After supervision and monitoring in 2019, our study showed improvement in awareness by over 97 %, which is better than the West Africa evaluation [
30]. In Zambia, Masaninga et al. concluded that door to door delivery of LLINs ensured availability of nets in hard-to-reach areas and provided a good opportunity to educate the members face-to-face. IEC/BCC activities during and after distribution played a key role in increasing compliance of LLIN usage amongst the communities [
31]. In this study, the mode of distribution of nets from one focal point in one village could not be changed to door-to-door delivery. However, it was ensured that the visits of Village Malaria Workers raised awareness using inter-personal communication techniques resulting in better usage of LLINs.
Regarding the reported adverse-effects of the bed-nets, a community-based survey in Uttar Pradesh found that 2.8 % of respondents reported itching and irritation by using the bed nets [
32]. In this study, complaints on adverse effects reduced from 26.7 to 9.6 % between 2017 and 2019, which is a reduction by 64 %. The significant difference can be attributed to use of IEC/BCC during the 2019, which informed the recipients about common expectations from the bed-nets in terms of adverse-effects and proper washing and drying techniques. It was noted that if the recipients are better informed about the LLINs, they exhibit better compliance.
Sood et al. found in Uttar Pradesh that use of smoke using similar methods was much more in villages where LLINs were not distributed as compared to those where LLINs were distributed [
32]. However, in the present study it was noticed that significant use of smoke was done as an alternative to LLINs. When asked the reason, respondents argued that LLINs only protect them during sleeping but to enjoy their evening time, they use smoke to ward off the mosquitoes. IRS and LLINs are equally effective interventions because study area had higher proportion
An. culicifacies, which is known to be an endophilic species [
17] and malaria transmission is maintained by this species from July to October.
Acknowledgements
We dedicate this paper to late Dr. Neeru Singh, past Director of ICMR- National Institute of Research in Tribal Health (ICMR-NIRTH), Jabalpur, who was the leading force in establishing this Malaria Elimination Demonstration Project. We are thankful to Director NVBDCP Dr. Neeraj Dhingra for his leadership and insights. We are thankful to the former Director General of ICMR and Secretary Department of Health Research, Dr. Soumya Swaminathan and present DG ICMR and Secretary Department of Health Research. Dr. Balram Bhargava for their support, insights and guidance. We are also thankful to the former Principal Secretary Health Mrs. Gauri Singh. the present Principal Secretary Health Dr. Pallavi Govil, and Health Commissioner Mr. Prateek Hajela, for their constant support for conduct of work in Mandla. We are also thankful to the District Magistrate of Mandla, Chief Medical and Health Officer Mandla, Police Superintendent of Mandla, CEO Zila Panchayat, Panchayat heads, ASHAs, ANMs for their encouragement and support in daily activities of MEDP. The authors are thankful to Mr Sekh Nisar, District Officer MEDP and Mr Vikesh Thakre, IEC BCC Officer MEDP for helping in successfully implementing the tool in the project areas. Thanks are also extended to District Malaria Officer and DVBD Consultant for attending training meetings and providing RDTs and ACTs for the project. The project could not have achieved its results without the support from Board of Sun Pharmaceuticals, FDEC India, core team of MEDP, community members, and media of Mandla district. The manuscript has been approved by the Publication Screening Committee of ICMR - NIRTH Jabalpur and assigned with reference number ICMR-NIRTH/PSC/11/2020.
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