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Birth Control For Mosquitoes – Is This The Malaria Cure?

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The buzzing of a single mosquito is enough to break a good night’s sleep.

So imagine when that same sound is multiplied a hundred times – it can at best be described as eerie.

Especially when these mosquitoes are in a white mesh cage, in a vacuum-sealed laboratory, and it’s around feeding time.

It is at this opportune moment that Lizette Koekemoer, dressed in a red jersey and white lab coat, sticks her hand into the cage.

While most would squirm at the thought of dozens of mosquitoes making a blood meal of your arm, Koekemoer hardly seems to notice. For her, feeding mosquitoes is as normal as breathing; she has done it so many times she no longer gets itchy from the bites.

“When you are working on them, you learn to appreciate them as a living organism. When you put a mosquito under a microscope, they are actually beautiful. I think people laugh when I tell them I work on mosquitoes and I get paid for it,” says Koekemoer.

For 23 years, Koekemoer has been at the forefront researching these insects across Africa. She is part of the Malaria Entomology Research Unit on the 10th floor of the Faculty of Health Sciences building at the University of the Witwatersrand in Johannesburg.

Koekemoer’s passion goes beyond the laboratory to barbeques where she gets excited to tell you what species you’ve just squashed on your leg, having been bitten more times than most she would know.

The reason we are here today, in this sealed laboratory with Koekemoer’s arm in a cage and mosquitoes sucking her dry, is to talk about a mosquito called Anopheles vaneedeni, discovered by her team on the Makhathini Flats, in northern KwaZulu-Natal (KZN).

“Anopheles vaneedeni has been known about since 1977, it has never – before now – been identified as a malaria-carrying vector in nature,” says Koekemoer.

Up until now it was thought two other mosquitoes, called anopheles arabiensis and anopheles funestus, were the main vectors of malaria transmission. Vectors are living organisms that can transmit infectious diseases between humans or from animals to humans.

Lizette Koekemoer sticks her arm in a mosquito-infested mesh cage in her laboratory. (Photo by Jay Caboz)

It is not just a new carrier species that has Koekemoer worried. On the rise are mosquitoes with an increased resistance to insecticides.

According to the scientist, conventional insecticide-based mosquito control methods, such as bed nets and repellents are now becoming redundant.

“A mosquito’s whole body is designed to keep it alive. If you have one female that has formed a resistance, when she lays eggs, you then have gene resistance going all over the place. You need to monitor this and then move on to a new insecticide to kill those ones.”

While these methods may have proven to be effective tackling funestus, which prefers to feed on humans indoors, it means arabiensis and now vaneedeni can never be completely eradicated. This is because both arabiensis and vaneedeni snack on people outdoors.

“All malaria species are active from dusk to dawn. That’s their peak period. As soon as the sun goes down, they start feeding. People socialize at night, when it’s warm. They don’t go to bed. Bed nets only protect you when you are sleeping. They don’t protect you when you are outside cooking and socializing,” says Koekemoer.

Sterilized males to combat malaria

Back in the lab, it is Koekemoer’s job to come up with ways of controlling malaria vectors. One of the team’s more radical solutions is sterilizing males with radiation.

“We’ve got a gamma radiator. So it’s fast and quick – 60 seconds. We put the pupae in a radiation chamber, put them on a jig and then one minute later, they are sterilized.”

Called the Sterile Insect Technique (SIT), Koekemoer wants to build a rearing facility that will pump out 50,000 sterilized males per week. Once nuked, these sterile males are reared and released into the wild to mate with wild females.

“At a small scale, it works really well. The key to this research is female mosquitoes mate only once in their lifetime and if the male is sterile, she will not produce viable eggs. It’s like birth control… In the lab we have up to 96% reduction in progeny,” says Koekemoer.

READ MORE: The Rat Race Against The Silent Killer

It has taken seven years of research to get to this point. Once built, Koekemoer estimates they would need R1.5 million ($113,000) to R2 million ($150,000) per year for SIT to run successfully.

“The thing to remember is a lot of research is done in colonized mosquitoes, in a controlled environment in a lab set-up. It’s difficult when you take this into the field, when your situation is a lot more complex and there is more than one species of mosquito,” says Koekemoer.

SIT was first used to control screwworm fly in America in the 1950s.

“It hasn’t been done with malaria, because malaria is complicated. Countries that are affected by malaria are also often not politically stable and financial resources are limited,” says Koekemoer.

The threat of new species?

Although vaneedeni’s emergence is worrying, it’s not yet time to panic.

“To put it into perspective, we collected a large number of species. So percentage wise, it’s not high. Out of the 3,000 we have collected, we had one KZN sample that was infected,” says Koekemoer.

Vaneedeni is also considered a minor vector because the mosquito prefers to feed on livestock rather than humans.

The question the team are trying to answer is why now? One theory they have is because of the changing environment in KZN. At the time the team found the mosquito, the area was drought-stricken.

“We need to look at the bigger picture of the environmental impact. Was it a once-off because it was so dry? That’s what we need to determine. Your environmental factors influence everything. Because there was drought, the impact on the number of cattle available, or the availability of water might have diminished, which is their preferred host and sites. If you are the only blood source, then the mosquito has no choice but to come to you and you could get affected,” says Koekemoer.

The field site is naturally isolated, between a mountain range and the ocean, in the Mamfene district 60kms from Sodwana and close to the town of Ndumu. A team member collects mosquitoes twice a week throughout the year. The mosquitoes fly into clay pot traps and are then catalogued by species.

“The fact that we now know about vaneedeni means we can target our research towards knowing more about this vector’s behavior,” says Koekemoer.

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Until effective controls for outdoor mosquitoes are developed, eliminating local malaria transmission in southern Africa will be extremely difficult.

“Thanks to other malaria control measures, the number of cases is down to around 9,000 per year from over 60,000 in 2000, but it has proven hard to bring the insect population – and infection rates – down any further using the traditional method of indoor residual spraying,” says Koekemoer.

“There are countries that have resistance to all the classes of insecticides. There are only four classes approved by the World Health Organization for mosquitoes. In some countries, there is resistance to all four classes. It highlights the need to invest and start looking into alternative control methods.”

Coming up with new methods is a race to diffuse a ticking time bomb.

“These genes will eventually move into our borders whether it is the mosquito or the parasite, it’s only a matter of time, it will come into South Africa. You need to be one step ahead. If something happens, what’s Plan B? ”

Thanks to a buzzing mosquito in a pot and a little radiation therapy, scientists are a step closer to solving the malaria malaise. Until then, it’s sleepless nights for them.

Mosquitoes suck blood from Lizette Koekemoer’s arm. (Photo by Jay Caboz)

Facts About Malaria

Malaria is a life-threatening disease caused by parasites transmitted to people through the bites of infected female Anopheles mosquitoes.

According to the latest WHO estimates, released in December 2016, there were 212 million cases of malaria in 2015 and 429,000 deaths.

The WHO African Region carries a disproportionately high share of the global malaria burden. In 2015, the region was home to 90% of malaria cases and 92% of malaria deaths.

In 2015, 91 countries and areas had ongoing malaria transmission.

Between 2010 and 2015, malaria incidence among populations at risk (the rate of new cases) fell by 21% globally. In that same period, malaria mortality rates among populations at risk fell by 29% globally among all age groups, and by 35% among children under 5.

Vector-borne diseases account for more than 17% of all infectious diseases, causing more than one million deaths annually.

[Source: WHO]

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Tasty Vegan Options: Consumed By Healthy Eating

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The restaurant market still hungers for healthy options. This entrepreneur is feeding that need, serving earth-conscious customers and gym junkies.  

Her desperation for a healthy meal fueled the fire for business.

Leigh Klapthor, 31, couldn’t find enough eateries that sold healthy food that was not bland, so decided to start her own.

“It is no fun to go out with friends and you are always the girl with the green salad,” she says.

“I wanted to find a way where being healthy is not such a chore and I also wanted for it to be affordable.”

Klapthor, who dropped out of a course in marketing communications at the University of Johannesburg, ditched a job in corporate marketing to pursue her passion for food.

A patron at Sprout Café. Picture: Gypseenia Lion

In 2017, she started Sprout Café at the Stoneridge Centre in Edenvale in Johannesburg with a loan she received from her husband’s business and money that was given to them as a wedding gift.

“Everybody underestimates what everything will end up costing [when starting a new business]. In my mind, I thought R150,000 ($10,588) would work. I thought I would get my shop fitting and everything done and in the first month we would be able to pay salaries with the money we make,” says Klapthor.

But she soon realized the unforeseen challenges faced by many entrepreneurs. She had to eventually pump in a capital of R350,000 ($24,706) to start the venture.

“So I had a couple of life lessons at the beginning. I had to end up using our savings but I didn’t mind having to do that because I trusted and believed in the vision.” 

But though she did, the banks did not because they often declined all her loan applications.

 “I think there are so many young black and enthusiastic individuals that have brilliant ideas and vision but the investment capital is not there. Though I do not have the capital as well to assist them, I would say keep going because the vision is greater,” Klapthor says.

Sprout Café offers health food, light meals, vegan food, and vegetarian and ketogenic diet food.

With her corporate marketing skills, she advertised her food on social media and gained a lot of traction.

“I want to create food on Instagram and people are like, ‘oh my God, I want to eat that’ and when they come into the store, it is the same deliverable they receive,” she says.

Sprout Café turns over R3 million ($211,677) annually and has 10 employees. 

After only two years of business, she has recently opened a second branch in the heart of the busy Moove Motion Fitness Club in Sunninghill in Johannesburg.

“There are people that are on specific diets and there is no one that is giving these people food. There is no one that is saying, vegan people want to be healthy too. They are making a conscious decision to preserve the environment and preserve their health and they are making these decisions but there is no one that is there to accommodate them.”

Klapthor says that the world is moving towards a plant-based lifestyle and she believes that many have recently caught on to that idea recently. 

Trend translator Bronwyn Williams of Flux Trends,  reiterates Klapthor’s views on how the world is adopting healthier habits. She believes that Generation Z is choosing good, clean fun the most.

“Yes, South Africa is not exempt from the global movement towards more locally-sourced and earth-friendly products and packaging,” Williams says.

However, Williams believes that because 64.2% of the South African population still lives in poverty, clean and organic food still remains costly for the majority of people.

“That said, unfortunately, earth-friendly consumer options remain a luxury that only the upper middle class can really afford to support and enjoy… certified organic, eco-friendly products tend to cost far more—up to 40% more than ‘regular’ packaged produce, it would be disingenuous to say that what the market wants is locally-sourced, earth-first produce when the majority of South Africans are struggling just to put any food on the table,” Williams says.

‘Every day, you should be able to eat a Sprout meal without having to feel any kind of guilt and shame,’ Leigh Klapthor says. Picture: Gypseenia Lion

Though Klapthor knows more people are opening healthy-eating establishments because they see that it is a trend, she believes that they need to be in touch with the reality of an ordinary person’s life and consider the cost implications.

“You can’t charge someone R150 ($10.59) for a Beyond Meat burger and expect her to come back tomorrow for the same burger. People are tight with their money and they work hard for it, they do not want to let go, for instance, of R500 ($35.29) in three days,” Klapthor says.

“We want to provide a healthy lifestyle, something that is consistent and that people can live through, and not just a treat-themselves-to at the end of the month. Every day, you should be able to eat a Sprout meal without having to feel any kind of guilt and shame.”

Obviously, it is a concept that has worked and keeps her business healthy as well.

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Young women in Soweto, South Africa, say healthy living is hard. Here’s why

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Data from South Africa has shown that over two thirds of young women are overweight and obese. This predisposes them to non-communicable diseases such as diabetes and hypertension. Most women are not exercising enough, and consumption of processed and calorie-dense foods and high amounts of sugar is common.

It was this knowledge that sparked the establishment of the Health Life Trajectories Initiative. It’s being run in South Africa, India, China and Canada and aims to provide interventions that can help young women stay healthy before, during and after pregnancy.

In South Africa, this randomised controlled trial will provide one-on-one support as well as peer group sessions to over 6000 young women. The idea is provide them with information, and to help them set and maintain goals for healthier lifestyles.

Researchers from the Medical Research Council and Wits University’s Developmental Pathways for Health Research Unit are running the South African arm of the study. We wanted to start by better understanding our target population – that is, young women aged between 18 and 24 living in Soweto.

READ MORE | Local Solutions Can Boost Healthier Food Choices In South Africa

Soweto is a large, densely populated urban township which comprises one third of Johannesburg’s population. Soweto is becoming rapidly urbanised, but the majority of people are still very poor and struggle to provide food for their families.

We conducted a series of focus group discussions and in depth interviews to unravel health behaviours, barriers and facilitators to wellbeing and health with young women from Soweto who had not yet had a child. We also asked them about what sorts of interventions they’d prefer to support and guide them.

The women offered important insights that showed it’s not enough to simply promote healthy eating and exercise without considering the very real environmental and structural constraints present in South Africa.

Barriers to healthy choices

The 29 participants spoke about many different facets of health. These included happiness and mental wellbeing, faith, social support, body image, and lifestyle behaviours.

They identified many barriers to healthy eating, among them the cost of and access to healthy food options. Some women also said they had little access to exercise facilities such as gyms and were afraid to exercise on the streets because they feared being assaulted or harassed. One woman said:

No, I don’t feel safe because we have drug addicts, traffic, women trafficking: it’s not safe for us to walk in the streets.

The women we interviewed painted a picture of an environment in which healthy behaviours are difficult to implement or sustain. One said:

Small businesses that are opening up in my community and they all sell fries, literally they just all sell fries…

Women told us that cheap and unhealthy fast foods are on every street corner: “bunny chow” – hollowed out bread stuffed with curry – vetkoek (a fried dough bread stuffed with different fillings) and fried chips are affordable and available within a few steps of most houses. As a result, women did not want to go out of their way to purchase healthier, more expensive foods.

Our interviewees also didn’t feel able to demand that healthier food be bought for their homes, because many were not contributing financially and were therefore not in a position to control food purchases. Women reported being financially dependant on relatives and male partners.

READ MORE | New Ways Of Thinking On Health, Arts And Humanities Are Emerging In Africa

Exercise

They also said that opportunities for physical activity were neither provided nor prioritised for women in Soweto. Some women said that a lack of facilities made it difficult for them to participate in any exercise, as they did not have access to gyms or fields to exercise.

Other women told us that there were gyms, sports grounds, parks, and even free aerobics classes at community halls in their area. However these facilities often get vandalised quickly, and can no longer be used. More importantly, they didn’t feel safe enough to exercise on the streets, perhaps by jogging or running. They also felt unsafe walking around in leggings or tights. Women were fearful of human trafficking, sexual assault, and violence – very real issues in this community.

Crucially, our research found that young women did not see obesity as a sufficient reason to change their behaviour. But they said they would be motivated to exercise and eat better if they were diagnosed with a non-communicable disease like diabetes.

This suggests that obesity has become normalised in South Africa – and this needs to be addressed.

Policy interventions

These findings are now being worked into our interventions, and we are cognisant of the contextual realities that may affect young women’s ability to change their lifestyles. We hope that this research, along with whatever findings emerge from our interventions, will inform policy makers and motivate them to implement necessary changes in this community.

Women in Soweto and in South Africa in general need support to live healthier lifestyles. This support needs to come from policy makers. If South Africa does not step up and support young women by providing them with access to safe spaces and affordable healthier foods, and by controlling the oversupply of unhealthy options, the country may not be able to curb its ever increasing rise in obesity and related non-communicable diseases.

-Alessandra Prioreschi: Associate Director and Researcher at the Developmental Pathways for Health Research Unit (DPHRU), University of the Witwatersrand

The Conversation

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Measles: Should Vaccinations Be Compulsory?

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Following a measles outbreak in Rockland County in New York State, authorities there have declared a state of emergency, with unvaccinated children barred from public spaces, raising important questions about the responsibilities of the state and of individuals when it comes to public health.

Measles virus is spread by people coughing and spluttering on each other. The vaccine, which is highly effective, has been given with mumps and rubella vaccines since the 1970s as part of the MMR injection. The global incidence of measles fell markedly once the vaccine became widely available. But measles control was set back considerably by the work of Andrew Wakefield, which attempted to link the MMR vaccine to autism.

There is no such link, and Wakefield was later struck off by the General Medical Council for his fraudulent work. But damage was done and has proved hard to reverse.

In 2017, the global number of measles cases spiked alarmingly because of gaps in vaccination coverage in some areas, and there were more than 80,000 cases in Europe in 2018.

Anti-vaxxer threat

The World Health Organisation has declared the anti-vaccine movement one of the top ten global health threats for 2019, and the UK government is considering new legislation forcing social media companies to remove content with false information about vaccines. The recent move by the US authorities barring unvaccinated children from public spaces is a different legal approach. They admit it will be hard to police, but say the new law is an important sign that they are taking the outbreak seriously.

Most children suffering from measles simply feel miserable, with fever, swollen glands, running eyes and nose and an itchy rash. The unlucky ones develop breathing difficulty or brain swelling (encephalitis), and one to two per thousand will die from the disease. This was the fate of Roald Dahl’s seven-year-old daughter, Olivia, who died of measles encephalitisin the 1960s before a vaccine existed.

When measles vaccine became available, Dahl was horrified that some parents did not inoculate their children, campaigning in the 1980s and appealing to them directly through an open letter. He recognised parents were worried about the very rare risk of side effects from the jab (about one in a million), but explained that children were more likely to choke to death on a bar of chocolate than from the measles vaccine.

Dahl railed against the British authorities for not doing more to get children vaccinated and delighted in the American approach at the time: vaccination was not obligatory, but by law you had to send your child to school and they would not be allowed in unless they had been vaccinated. Indeed, one of the other new measures introduced by the New York authorities this week is to once again ban unvaccinated children from schools.

Precedents

With measles rising across America and Europe, should governments go further and make vaccination compulsory? Most would argue that this is a terrible infringement of human rights, but there are precedents. For example, proof of vaccination against yellow fever virus is required for many travellers arriving from countries in Africa and Latin America because of fears of the spread of this terrifying disease. No-one seems to object to that.

Also, on the rare occasions, when parents refuse life-saving medicine for a sick child, perhaps for religious reasons, then the courts overrule these objections through child protection laws. But what about a law mandating that vaccines should be given to protect a child?

Vaccines are seen differently because the child is not actually ill and there are occasional serious side effects. Interestingly, in America, states have the authority to require children to be vaccinated, but they tend not to enforce these laws where there are religious or “philosophical” objections.

There are curious parallels with the introduction of compulsory seat belts in cars in much of the world. In rare circumstances, a seat belt might actually cause harm by rupturing the spleen or damaging the spine. But the benefits massively outweigh the risks and there are not many campaigners who refuse to buckle up.

I have some sympathy for those anxious about vaccinations. They are bombarded daily by contradictory arguments. Unfortunately, some evidence suggests that the more the authorities try to convince people of the benefits of vaccination, the more suspicious they may become.

I remember taking one of my daughters for the MMR injection aged 12 months. As I held her tight, and the needle approached, I couldn’t help but run through the numbers in my head again, needing to convince myself that I was doing the right thing. And there is something unnatural about inflicting pain on your child through the means of a sharp jab, even if you know it is for their benefit. But if there were any lingering doubts, I just had to think of the many patients with vaccine-preventable diseases who I have looked after as part of my overseas research programme.

Working in Vietnam in the 1990s, I cared not only for measles patients but also for children with diphtheria, tetanus and polio – diseases largely confined to the history books in Western medicine. I remember showing around the hospital an English couple newly arrived in Saigon with their young family. “We don’t believe in vaccination for our kids,” they told me. “We believe in a holistic approach. It is important to let them develop their own natural immunity.” By the end of the morning, terrified by what they had seen, they had booked their children into the local clinic for their innoculations.

In Asia, where we have been rolling out programmes to vaccinate against the mosquito-borne Japanese encephalitis virus, a lethal cause of brain swelling, families queue patiently for hours in the tropical sun to get their children inoculated. For them the attitudes of the Western anti-vaccinators are perplexing. It is only in the West, where we rarely see these diseases, that parents have the luxury of whimsical pontification on the extremely small risks of vaccination; faced with the horrors of the diseases they prevent, most people would soon change their minds.

Tom Solomon; Director of the National Institute for Health Research (NIHR) Health Protection Research Unit in Emerging and Zoonotic Infections, and Professor of Neurology, Institute of Infection and Global Health, University of Liverpool

-The Conversation

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