By Dianne Tipping-Woods
Malaria is as deadly as ever in the South African Lowveld. With already 11951 cases and 82 deaths recorded in Limpopo and Mpumalanga, this year is significantly worse than last year and at a similar level to 2014 and 2015. Babies and children are especially vulnerable and experts agree that the only way to locally combat the disease is for private residents to self-organise and to spray at least 80 percent of all properties in a certain area, using the correct, World Health Organisation-approved residual insecticides.
Despite the summer season generally being regarded as the period with highest transmission, June 2017 was particularly bad, notes Professor John Frean of the National Institute for Communicable Diseases. Malaria is a statutory notifiable disease, which means that cases in provinces where malaria is endemic are reported to and investigated by the provincial malaria control programmes and provincial departments of health.
Philip Kruger, from the Limpopo Department of Health in Tzaneen confirms that the control programmes have detailed local information about cases and where malaria ‘hotspots’ are. Their insecticide spraying programmes target known and expected areas of transmission. However, he adds that the disease still has the ability to surprise, and the 2017 Easter period was an example of this, with case numbers rising over a period when they are usually in decline. They rose again in early to mid August and could be on the rise again.
“Ideally we want to isolate hotspots and stop an outbreak, but in August for example, cases were scattered over a wide area and not linked to a hotspot.” As such, he advises treating all areas equally: “We can’t predict where it will crop up. Malaria can do unexpected things.”
Kruger maintains that local action has a significant role to play in reducing malaria risk:
“Houses need to be treated with an insecticide on the inside surfaces. Places where mosquitoes breed need to be identified and eliminated and ideally the human hosts of malaria need to be found and treated, as humans are the natural hosts of malaria, with Anopheles mosquitoes only responsible for transmitting malaria from one human to the next.”
According to Kruger and Francois Maartens from Integrated Malaria Control Consulting (IMCC) , for indoor residual spraying to be effective, at least 80 percent of houses in an area need to be sprayed.
Professor Frean agrees that indoor residual spraying is the most effective method of malaria control and has been highly successful in controlling malaria in South Africa, but he concedes that “as with all national public health efforts, there are always budgetary and other constraints that affect the malaria control programmes.”
To control malaria in Hoedspruit and minimise risk, Kruger advises “spraying must become a way of life”. He said that The Malaria Institute has budgeted R100 million and appointed 340 workers for its vector control programme in 2017, “but we are dealing with a very vast area over an extended period of time. Our focus remains on bigger communities. Some farm areas around Hoedspruit are covered, but this stretches our resources to the maximum.”
Given these constraints, residents have the option to self organise and Kruger encourages them to do so. This should be done in a coordinated way as far as possible, to ensure that it is effective, cautions Maartens. He notes that several factors need to be considered before an insecticide is selected for IRS such as vector susceptibility, residual effect, excito-repellency, availability, cost and safety. “Indoor residual house spraying coverage refers to the percentage houses sprayed in an area. The ideal situation would be to spray every single house; however spray coverages of 80% is seen as the gold standard for effective IRS malaria control.”
Indiscriminate spraying with the wrong equipment and insecticides can have negative consequences in the long-term, although as Frean suggests, “insecticide spraying is generally regarded as safe when properly carried out. The alternative (i.e. no indoor residual house spraying) is uncontrolled malaria epidemics that will lead to large numbers of malaria cases with accompanying increases in mortality”. Residual insecticides are not able to differentiate between species, however, by applying insecticide indoors “it is kept out of the physical environment,” minimising possible negative environmental contamination. This is a list of WHO approved specifications for pesticides used in public health. “I still have to see a pest control company doing correct/scientific malaria control so would not advise using them until they are assessed,” cautions Maartens. This is a microbial insecticide (biological agent) for the control of mosquito and fungus gnat larvae in their breeding sites that does only affect target species.
“Resistance is also a real concern; we don’t have many tools in our tool box,” says Kruger. “On a micro level through in an area like Hoedspruit, where residents are using pyrethroids, I wouldn’t be too worried about resistance building up.”
Well-managed IRS alone is not enough and experts advocate an integrated malaria vector control program, such the programs run by Integrated Malaria Control Consulting (IMCC), which consists of the following malaria control intervention methods:
- Indoor Residual House Spraying (IRS).
- Larvaciding. Various larvacides have been developed to kill mosquito larvae before they hatch and no risk to human health, non target species and the environment if the products is used according to the label directions.
- Fogging (space spraying). According to Integrated Malaria Control Consulting (IMCC), the various fogging solutions have been developed to kill adult mosquito and pose limited health risk to humans if the products are used according to the label directions.
- Environmental management. This is a combination of different activities performed by trained environmental management operators to reduce the amount potential mosquito resting and breeding sites in a control area.
- Personal protection. This includes limiting outdoor exposure between dusk and dawn; covering skin with appropriate clothing; applying DEET-containing repellents to exposed skin; using insecticide coils, mats and sprays indoors; screening windows and doors against mosquitoes; and remembering that ‘flu-like’ illness might be malaria, and obtaining necessary medical care.
For an update on government spraying in your area contact the Malaria Institute at 015 3073737. According to Masilo Frans Phoshoko, there are teams at work and “everyone has a right for their households to be sprayed, more especially by government programmes”. According to Phoshoko, the teams for the Hoedspruit area are stationed at Willows Clinic and Sekororo Hospital. The service is free as it is offered by the Malaria Institute as part of their vector control programme under the auspices of the Department of Health in the province. You can contact one of the station managers Julias Ngobeni on 082 8155004 or alternatively you can call the institute in Tzaneen at this number 015 3073737.
In addition, follow these tips on MINIMISING LOCAL MALARIA RISK (read this article in full for lots of extra info, not included in this post). If you have additional questions, please let us know and we’ll try and get some answers.
- Houses in risk areas need to be sprayed on the inside with chemicals with a residual efficacy, for example Deltamethrin or Alpha-Cypermethrin. Pest control companies can assist the community with this. If a larger part of the community is prepared to organize itself, the Department will be prepared to provide training in this regard. Kruger specifically mentioned members of management or maintenance teams of residential estates and game lodges, who can be trained to effectively spray against malaria. Integrated Malaria Control Consulting (IMCC) also offers this service.
- Breeding places of mosquitoes need to be eliminated. There options to eliminate breeding spots are: removing standing water (even tiny amounts), using chemicals or using products containing specific bacteria (Bacillus thuringiensis israelensis), as a biological control method. The first and the last options are environmentally friendly, with the biological control suitable for pools in river beds and larger pools around streams and wetlands. When using Bacillus thuringiensis israelensis, the mosquito larvae feed on the bacteria, which can be applied to standing water in granule form and prevent the larvae from maturing into adult mosquitoes .
- The suspected carriers of malaria should be traced and treated. According to Kruger, through many years of intense malaria control, the disease is not prevalent in local communities in South Africa. It is suggested that the malaria parasites are brought into our communities through migrants from countries with little or no malaria control. Industries or companies that employ (casual) labour from malaria endemic countries can make a huge difference by having these workers tested and when found positive – treated. Employers should help educate and protect their employees by sharing information on how to prevent malaria and seek treatment at the first sign of the disease.
- Take precautions. Install gauze in front of open windows and doors and make sure the house is closed from sunset to sunrise. The malaria mosquitoes don’t fly or feed during day time Have your house’s interior walls treated (sprayed), use mosquito mats and insecticide treated mosquito nets. Strict precautions can reduce your risk to “almost zero percent” says Kruger.Personal precautions against malaria include limiting outdoor exposure between dusk and dawn; covering skin with appropriate clothing; applying DEET-containing repellents to exposed skin; using insecticide coils, mats and sprays indoors; screening windows and doors against mosquitoes; and remembering that ‘flu-like illness might be malaria, and obtaining necessary medical care. When travelling to areas of high transmission, appropriate chemoprophylaxis should be considered. According to the people consulted to obtain information for this post, herbal and homoeopathic products are not effective in preventing or treating malaria. Citronella oil is not very efficient as a repellent.
- When outdoors at night or in areas not screened from mosquitoes, apply mosquito repellents to ALL exposed skin, using products like Peaceful Sleep or Tabbard. Citronella based repellents are not as effective, according to Kruger.
- Be overprotective when it comes to babies and small children and request malaria tests when observing malaria symptoms like fever, headache, body pains, vomiting and diarrhea.
Frean notes that South Africa is aiming to eliminate malaria in the next few years. This is discussed in the NICD malaria booklet and in the following comprehensive malaria issue: South African Medical Journal 2013 (Vol. 103 No. 10) (available online (open access) at samj.org.za). The Supplement is called Malaria: Control to Elimination.
More general information about malaria and its prevention is available on the NICD website, including, currently malaria FAQs and a malaria season update. There is also a comprehensive booklet about malaria produced by the NICD (under Malaria in the Diseases A-Z link). The SA Society of Travel Medicine website (http://www.sastm.org.za/) also carries information about malaria prevention.
Note by the editors:
We’ll update this post with more information when we get additional answers from the Malaria Institute, National Centre National Institute for Communicable Diseases, Integrated Malaria Control Consulting and the other sources we have contacted for a) specific local information b) more information/follow-up questions.