New publication! Snakebite victim profiles and treatment-seeking behaviors in two regions of Kenya: results from a health demographic surveillance system in Tropical Medicine and Health (BMC)
Permanent injury from a puff adder bite, Kenya, 2016
Back in 2016 or so, I nearly stepped on a headless and very dead spitting cobra on an island in Homa Bay, Kenya. The locals apparently weren’t satisfied with simply decapitating it, but smashed the head to bits presumably so it couldn’t come back to life and bite someone. That gave me a hair brained idea to do a research project on snakebites and I’m proud to say that the results of that work have been published today.
This work was a team effort under the auspices of the Nagasaki University Institute of Tropical Medicine. It couldn’t have happened without the incredible contributions of researchers, students and local partners,in Kenya, Japan and the United States.
Snakebites are a major cause of permanent injury and death among poor, rural populations in developing countries, including those in East Africa. This research characterizes snakebite incidence, risk factors, and subsequent health-seeking behaviors in two regions of Kenya using a mixed methods approach.
As a part of regular activities of a health demographic surveillance system, household-level survey on snakebite incidence was conducted in two areas of Kenya: Kwale along the Kenyan Coast and Mbita on Lake Victoria. If someone in the home was reported to have been bitten in the 5 years previous to the visit, a survey instrument was administered. The survey gathered contextual information on the bite, treatment-seeking behavior and clinical manifestations. To obtain deeper, contextual information, respondents were also asked to narrate the bite incident, subsequent behavior and outcomes.
8775 and 9206 households were surveyed in Kwale and Mbita, respectively. Out of these, 453 (5.17%) and 92 (1.00%) households reported that at least one person had been bitten by a snake in the past 5 years. Deaths from snakebites were rare (4.04%), but patterns of treatment seeking varied. Treatment at formal care facilities were sought for 50.8% and at traditional healers for 53.3%. 18.4% sought treatment from both sources. Victims who delayed receiving treatment from a formal facility were more likely to have consulted a traditional healer (OR 8.8995% CI [3.83, 20.64]). Delays in treatment seeking were associated with significantly increased odds of having a severe outcome, including death, paralysis or loss of consciousness (OR 3.47 95% CI [1.56; 7.70]).
Snakebite incidence and outcomes vary by region in Kenya, and treatment-seeking behaviors are complex. Work needs to be done to better characterize the spatial distribution of snakebite incidence in Kenya and efforts need to be made to ensure that victims have sufficient access to effective treatments to prevent death and serious injury.”
Are dogs associated with infections by a skin burrowing flea in Kenya? Masanobu Ono and I with Kensuke Goto, Satoshi Kaneko, mwatasa Changoma just published a paper on #tungiasis in the journal Tropical Medicine and Health.
Most people haven’t heard of tungiasis, an ectopic skin disease caused by the skin burrowing parasite, T. pentrans. It causes itching, pain, is associated with serious secondary bacterial infections, gangrene, social exclusion and debilitation. It primarily afflicts the very young and very old and is found almost exclusively in the poorest parts of the poorest parts of the world. It fits the classic definition of a neglected tropical disease.
We explored associations of wildlife and domesticated animals with household level tungiasis in Kenya using a two stage complex sampling based survey in an area adjacent to a wildlife preserve.
Tungiasis is a ectopic skin disease caused by some species of fleas in the Tunga genus, most notably T. penetrans. The disease afflicts poor and marginalized communities in developing countries. Transmission of tungiasis comprises a complex web of factors including domesticated animals and wildlife. This research explores animal and environmental risk factors for tungiasis in an area adjacent to a wildlife reserve in Kwale, Kenya.
A two-stage complex sampling strategy was used. Households were selected from three areas in and around Kwale Town, Kenya, an area close to the Kenyan Coast. Households were listed as positive if at least one member had tungiasis. Each household was administered a questionnaire regarding tungiasis behaviors, domesticated animal assets, and wild animal species that frequent the peridomiciliary area. Associations of household tungiasis were tests with household and environmental variables using regression methods.
The study included 319 households. Of these, 41 (12.85%) were found to have at least one person who had signs of tungiasis. There were 295 (92.48%) households that possessed at least one species of domesticated animal. It was reported that wildlife regularly come into the vicinity of the home 90.59% of households. Presence of dogs around the home (OR 3.85; 95% CI 1.84; 8.11) and proximity to the park were associated with increased risk for tungiasis infestation in humans in a multivariate regression model.
Human tungiasis is a complex disease associated with domesticated and wild animals. Canines in particular appear to be important determinants of household level risk.
Humans have had to deal with the threat of snakebites as long as humans have existed. While deaths from snakebites are rare, the outcomes are so severe and the nature of the animal so mysterious, that humans have developed all sorts of ways of dealing with them.
Witchdoctors, or Mganga as they are known in East Africa, are the first line for snakebite treatment here. The Waganga are fairly useless for treating many serious health issues, but they have carved out a niche for themselves for a few public health problems.
Our survey in Western Kenya confirms that nearly 100% of people who have been bitten by a snake visit the Mganga, regardless of whether they visit a formal health facility or not.
I went and sat down with an established Mganga here in Kwale and he was gracious enough to answer all of my questions openly and (mostly) honestly.
Hello, thank you for taking the time to speak with me today. Is English OK?
No, my English is not very good. Can we do this through a translator?
Of course. So, what happens when a patient comes in for treatment for a snakebite?
When the patient comes in, I first apply the “njiwe na njoka” (lit: snake stone). The stone sucks all the poison out of the wound. When you put it on the bite, it will stick. When the stone has absorbed all the poison, it will fall off.
What do you mean? Like it just sticks to the flesh without tying it?
Yes, if there is poison, the stone will stick to the body. When all the poison is gone, the stone will fall off. After it is done, I take the stone and wash it with milk several times and then use it again for the next patient.
What is the snake stone? Is it like a rock? I’ve seen people use charcoal in the villages. They tie it to the wound, it doesn’t appear to stick on its own.
No, this is different. This is a stone from the snake. The stone is in the skull of the snake, like that of a fish.
(Note: I did not know this, but some species of snakes have otoliths, like most fish. Snakes (and fish) are deaf in the traditional sense. The otolith is a piece of calcium which grows as the animal ages and sit on top of a bed of nerves. When there are vibrations, the otolith vibrates, stimulating the nerve bed so that the animal can “hear” motion around it. Not all snakes have otoliths but some species of burrowing snakes do.)
Where do you get the stone? Can you just buy it in the market?
The snake stones come from the Maasai, from big snakes in Maasai land. My teacher travels to Maasai land to get them and brings them back.
If the wound is fresh, I apply the stone. However, if it has been two or three days since the bite, I can’t use the stone anymore. Then I have to use a special medicine made from herbs and crushed snake heads. I mix it all together, then crush it into a powder and keep in a gourd.
When the patient comes in, I use a new razor blade to make small scratches on the wound. Then I rub the powder in it and bandage the wound. The wound will try to heal over time, so you have to make the scratches to be able to apply the powder.
Do you use the razor blade again?
No, I always use a new blade. (He was emphatic on this point.)
What is the powder made from?
Snakeheads. When we kill a snake, we keep the heads to make the powder. We mix it with roots, bark and leaves from special plants from deep in the forest. My teacher is a security guard in one of the forests and can get them when he can find them.
Wait, so your teacher is a forest ranger? Can’t he get by being an Mganga?
Yes. He is a forest ranger.
So he took the job so that he can get the plants from the forest whenever he needs them.
OK, so how many bites do you see per month?
It depends, some months I get more than others but mostly one every three months or so.
Do you refer them to the health facility for formal treatment?
Yes, I do. I treat them, then they go to the facility, then they come back to me. (I’m suspicious on this point, though the Mganga in question appears more together than most.)
Is there a religious component to this?
Well, there are two kinds of bites, those where the snake just bites and there is no witchcraft and those where someone has used magic to send the snake to bite you.
How do you know the difference?
If the bite heals quickly, there is no witchcraft. But if the bite is treated and does not improve then there is definitely witchcraft involved. At that time, I have to use powerful magic to get rid of the curse.
What do you do?
I send the snake back to the person who applied the curse. When we hear that someone nearby has been bitten, we know who applied the curse.
(Note: this is not uncommon. Witchcraft is often associated with hatred and revenge but the person applying the curse risks becoming cursed themselves. It is possible that snakebites are seen as a never ending battle of malevolent spiritual forces. What this does is sow distrust among people, even families and the Mganga is seen as the only cure. The result is that the Mganga are never without work.)
How did you learn this craft?
I was sick for a long time with stomach and head problems. I went to the hospital and it never got better so then I went to an Mganga. I improved. The Mganga suggested that I become on and I started training under him.
Thank you very much for your time.
We just spent the day driving around Kwale looking for snakes, and/or people who had been bitten by snakes. As the last post showed, snakebites are a persistent problem along the Kenyan Coast, with more then 5% of the households we survey indicating that at least one person in the household had been bitten in the past two years.
It wasn’t difficult to find them.
Snakes are universally feared all over Africa and the associations with witchcraft make it a common topic of discussion. Everyone knows someone who has been bitten. They often know all the details, including where it happened and what occurred following the bite. It’s never a happy story.
We went deep into Kinango, an extremely rural area west of Kwale Town and found a friendly lady who seemed to know everything about everyone. She was incredibly jolly, pulled out some plastic chairs for us to sit under and cracked jokes the whole time. I even got to copy her collection of Sangeya music which she had recorded on her phone (another post but you can hear some of it here) at some local music festivals. In total I got more than five hours of live Sengeya and Chilewa music. In the music world, these would be called “field recordings.” Here, this is just music she cooks and cleans to.
Switching back and forth between snakes and Sengenya (in Africa it seems to be possible to have multiple conversations at once), she told us about a kid who had been bitten two days previous. She even told us where to find her, so off we went.
The child was collecting firewood around a mango tree near her home, when she was suddenly bitten by a large green snake, not once but three times on the foot. The snake bit once skated away, decided it wasn’t enough and came back and bit her twice more.
Ants had moved into the dead tree and hollowed out the area underneath. Presumably, the snake moved in previously and came out to warm up during the day.
The mother thankfully took the child immediately to Kinango Hospital and treated was administered. The child was given a three day course of antivenom injections and charcoal was wrapped around the wounds to absorb any venomous discharge. Though the child complains of some numbness in the area, it looks as if there won’t be any permanent damage. Thankfully.
We were also told of an old woman who had been bitten more than 20 years ago, and was badly scarred, figured out where she was and off we went again.
As we pulled up a friendly young lady came out to greet us, and showed us the way to the house out back. In the distance, we could see an old lady walking with a limp. Otherwise, she was completely fit and seemed to be cutting her own firewood with a panga.
She brought us out some chairs and sat down to chat. In 1992, she had been out back collecting firewood (a pattern) and was bitten on the foot by puff adder, one of the deadliest snakes in the world. She was bitten on the foot, and became immobile for nearly a week. A series of witch doctors were brought in, who administered charcoal rubbed into small cuts in the skin.
Necrosis set in, and watery blood erupted out of the wound site. A large number of maggots appeared. Finally, someone had the good sense to take her to the hospital, where she spent an entire year.
The details were unclear, but it appeared that the gangrene was so severe that multiple infections were presents. They likely had her on intravenous antibiotics for an extended amount of time. Despite this, the foot did not heal. Some Christian missionaries came, and convinced her to convert to Christianity, which, she claimed, improved her condition. This is likely coincidental.
The doctors suggested a skin graft to improve the foot, but she refused. Necrosis was so deep that it permeated the bone and the foot is permanently curved as a result. The leg still shows sign of swelling even more than 24 years after the bite. In most cases, they probably would have simply amputated.
The lady was born in 1948, bore ten children, one of which was born just as she was bitten. She was unable to breast feed or care for the child. Regardless, the daughter has two children of her own now.
Snakebites are bad news. In this woman’s case, the disregard for proper medical care simply made a bad situation worse. She is truly lucky to be alive. If she had died, it is doubtful that the Mgangas would have admitted any responsibility.
I sent our DSS out looking for snake bites, and they found them! We simply asked households if anyone in the household had been bitten by a snake in the past five years. More then 5% of them said “yes” and since we know the locations of the households, we were able to make this cool map. Note that the snake bites tend to cluster around two large areas and are noticeably absent from others.
Kenya hosts many varieties of extremely poisonous snakes included the Puff Adder, the Black and Green Mamba and the spitting Cobra. Snakes are universally feared here and often killed on sight by the locals.
I wanted to go and see what this jigger thing was really about so I had my guys rent a car and we drove into Mtsangatamu town. Mtsangatamu (I still can’t pronounce it properly) lies along the edge of the Shimba Hills Wildlife Reserve and, according to my data, is a hot spot for tungiasis, or infections from the so called “jigger flea.”
It is a beautiful area. Filled with tropical trees and overgrowth, the landscape looks almost uncontrollable, despite the soil being so sandy that not a drop of water stands anywhere. The air is blistering hot.
People don’t get out here much, though the packed buses that pass by every few minutes indicate that the area isn’t entirely isolated. We drop off some gas for one of our drivers, who has to slowly fill his tank, drop by drop, with the tiniest of plastic funnels. Some development project should provide proper plastic funnels to these guys.
For some reason, we drive into the bush along a foot path, until we find ourselves wedged between a number of small pine trees. “We have to walk now,” I am told while I wonder why we drove this far anyway. Walking would have been easier.
We exit the car, walk through what a patch of neatly arranged trees. A tiny tree farm. I never see this in Western, ever. Coming out, we walk into a compound laid out in a manner wholly uncharacteristic of Kenya. A two story building sporting an upstairs patio complete with a winding staircase to the top, the place looked like the type of patchwork architecture that you associate with off-gridders in the US rather than Kenyan peasants.
The Mighty Paraffee turns out to be a kid of about 24, chilling out in the shade. He built this place himself, installed power, has a guest room and an upstairs shower and toilet. His room is decorated with reggae stars and pictures of the saints. Indian music is blaring out of the building. I’ve seen creative interiors from reggae fans in Kenya, but this is something else. This kid should be in architectural school. He even made sure to place the building under a giant tree to keep it cool.
I never figure out what the family does for money and no one can tell me, but the mother is exceedingly proud.
No jiggers here. We walk on. After about a kilometer, we find a poor family sitting outside their house. Children aren’t in school and no one speaks any English indicating that none of them go.
Hassan (one or our workers) brings over a little girl and tells me to look at her feet. Fatuma is 10 years old and her feet are infested with jiggers. She says the don’t hurt much in the day, but they itch at night. Her brother apparently has them, too. Her mother and her aunt do not.
Everyone is barefoot and they all sleep in the same house. I’m wondering if there might be something about the skin which makes kids susceptible while adults are spared.
I notice a group of goats in a pen and start asking questions about animals.
Tungiasis is a zoonotic disease. It is passed from wildlife to domesticated animals to people who bring it into the household and infect their other family members. Or so it is though. Not many people have really explored the question sufficiently. Of course, this is why I’m here.
They have about 15 goats, a few chickens and I notice a young dog and a cat walking around. I ask if they ever notice whether the dog ever has jiggers. They say no.
“What kinds of wildlife do you see around here?” One of the kids was killed by an elephant last year. There are wild dogs and hyenas which come and try to get the goats. Wild pigs dig up the cassava at night.
Pigs. That has to be it. A big mystery has been why there is such a tight relationship between distance to the park and jiggers infections. Wild pigs come out of the forest, raid the fields of the locals and get water from the river, and then recede back into the darkness before morning. 5km is approximately the distance that a pig could feasibly travel and return home in one night.
Pigs travel through and around the compound, dropping eggs, they mature and are probably picked up by dogs, but are most likely picked up by kids walking in the bush. They then bring them back home and pass them on to their family members.
Hassan associates jiggers with mango flowers, but I probe him further and find that the flowers coincide with the very dry season, which could explain why pigs are making the trek to the river and why they prefer the fields since both water and food are probably scarce in the forest.
I have to send a student out to investigate this further.
An old man comes out. He looks nearly 90, but is mostly likely on 60 at most. He has arthritis in his back. He shows me his feet which are moderately infected, mostly only between the toes. He asks for medicine. I tell him I’ll send some along. He offers me some boiled cassava which I graciously take. My colleague refuses because there are no cashew nuts with it, but I suspect that he’s worried about getting sick. I become concerned.
We take some pictures and go.
On the way back, we run into an elderly lady. She’s sitting next to her husband, who is busy getting lit on homemade beer at 11 in the morning. She shows me her feet. The spaces around her feet are infested with jiggers. It must be horribly painful.
She points out that she doesn’t have a whole lot of feeling in her left foot. I notice that her skin in this area is clear; the bone is visible through her skin. I ask what happened. She says that she got bitten by a snake 40 years ago. She was pregnant. I ask her if the baby was ok. “The baby is standing there!”
I consider making a joke about a snake baby, but think better of it. I’m just amazed that both of them survived. The wound was horrible looking.
Somehow, we manage to pull ourselves out of the trees and move on. There are some baboons removing mites from one another on the road on the way back, and I take some pictures. My colleague is about to pass out from the heat. I offer to drive.