There are plenty of decisions to make before leaving on a big bike trip, and we've put a good bit of research into making (what we think are) the right decisions for us. After we're on the road a bit, we'll update posts like this one with whether what we thought was a good idea actually turned out to be a good idea. Of course, there are people far better qualified than us (physicians, more experienced bike travelers) whose opinions should hold greater weight. This is what we're planning to do, not necessarily what you (if you're going bike touring) should be doing.
With that out of the way:
Let's talk about malaria.
Malaria is virtually nonexistent where we're from (America), but pretty endemic in many parts of the world. Carried by humans and mosquitoes and transmitted between humans by mosquitoes, over 3.2 billion people across 106 countries live in areas at risk of malaria transmission. Though it's both preventable and treatable, malaria still infects about 214,000,000 individuals per year and kills about 440,000.
Malaria can be prevented in two ways. The first is avoiding mosquito bites altogether: covering your skin with clothing, covering your face with a headnet, sleeping under cover of a bednet or tent, and using insect repellent (particularly one with DEET). The second is by taking antimalarial prophylactics—malaria pills—every day (or week, depending on the type of pill). These pills reduce (but don't eliminate) the ability for the malaria parasite to grow and replicate in your body.
On our bike trip through many malaria-endemic regions, we plan on preventing mosquito bites by covering up and using bug spray, but not by taking prophylactics. Here's why.
All prophylactics have pretty frightening side effects.
Malaria pills often come with side effects that are worse than malaria itself. Common reactions to doxycycline include stomach upset, diarrhea, nausea, vomiting, increased likelihood of sunburn, difficulty swallowing, and kidney problems, while less common (but really serious) side effects include permanent blindness, ulcers of the esophagus, severe intestinal conditions, and recurring yeast infections. Malarone presents similar risks, along with general weakness, loss of bladder control, hives, convulsions, chills, skin lesions and rashes, a quickened heartbeat, and sensitivity to light (I took malarone for a week in India, felt terrible, and promptly stopped). Taking chloroquine adds the chance of going deaf and having seizures, and mefloquine (which must now be sold with a boxed warning listing its psychological risks) is known to cause anxiety, paranoia, auditory and visual hallucinations, vivid dreams, and disassociative behavior that's believed to have caused at least one mass shooting.
These side effects all increase in likelihood and severity with long-term use (though they can also appear very quickly). As we make our way slowly around the world through regions with different strains of malaria parasites (resistant to different types of malaria medication), we would need to rely on several of these prophylactics for extended periods of time, each with its own potential to react poorly with our chemistry.
The risk of getting malaria isn't that great.
Of course, the common refrain here is that sure, there are side effects, and yes they can be very serious, but most people don't experience any of the above. But the probability of actually being infected by malaria is even lower. Of the 3.2 billion people living in areas at risk for malaria transmission, the 214 million that get infected—though a shockingly high number—is just 0.7% overall. And of those infected, the 440,000 who die make up just 0.002% (or an infinitesimal 0.0001% of those at general risk). The chances of experiencing negative side effects of mefloquine, by contrast, are about one in ten.
(EDIT: It's worth pointing out that local populations generally have a stronger resistance to malaria than travelers, and also that malaria-endemic countries can under-report cases of infection due to poor reporting, non-standardized care, or fear of scaring away tourists. That said, travelers are more likely than the local population to remain vigilant in other ways, like regularly applying repellent or sleeping under bed nets. The percentages above are overly general, and so it's difficult to say precisely what the true risk of getting malaria in any one place may be.)
Prophylactics aren't fully effective at preventing malaria.
Sure, the risk of getting malaria might be low, but bike tourers—who spend a good deal of time outside—are probably a high-risk category. Taking the gamble of adverse effects for a full-effective preventative is one thing, but the reality is that prophylactics just aren't that effective at protecting users from becoming infected. Again, the malaria parasite grows ever more resistant to antimalarials each year, and mosquitoes don't always adhere to the boundaries set by health professionals who determine prophylactic A is the best preventative for region X and prophylactic B is the best preventative for region Y. Navigating malaria country would require juggling all four prophylactics in our panniers and matching those against what's most likely to be present (and not yet antimalarial-resistant) where we are at any moment, all the while, once more, exposing us to prophylactics' harmful side effects.
Antimalarials can mask (or imitate) the symptoms of malaria.
If you're taking antimalarials and enjoying no real side effects, that's great. But if you get malaria anyway, those same antimalarials can actually mask the symptoms of the disease, like taking decongestants while you have a cold. Conversely, if you're taking antimalarials and suffering from side effects like headaches, nausea, fatigue, and vomiting (common reactions to the pills), you could easily mistake the symptoms of malaria for side effects of the prophylactics.
Malaria, if treated promptly, actually isn't that dangerous. Only one of the four strains of malaria is lethal, and those who die from malaria (assuming good health to begin with) die because they don't have access to treatment, were not properly diagnosed, or did not seek help because they didn't know they had malaria. Thus, a pill that masks or imitates the symptoms of malaria can be really dangerous, and make malaria seem worse than it actually is.
The risk of actually having malaria isn't that great.
Full disclosure: I have not had malaria (yet), and those who have may have had a really miserable time of it and really wish they'd taken their antimalarials. But having studied this subject for months—including reading a whole lot of first-hand accounts—the consensus seems to be that malaria (again, if promptly diagnosed and treated) is a bit like having the flu: it really sucks for a little while, but it's not a death sentence and it's not childbirth and more often than not, everything will be okay.
Here's a story about a woman who regrets not taking malaria pills. She was in India, she stops her prophylactic regimen, she gets malaria, and she gradually starts feeling its symptoms. She becomes weak yet keeps traveling, and after another two weeks decides to head home. It takes her another week to reach Delhi. Symptoms worsen. She stays in Delhi for about a week, both not seeking and actively resisting treatment (with the subtle implication that Indian doctors can't be trusted to administer a shot, which I can say from firsthand experience is not true), before finally flying all the way from India back to England without treatment. Finally, she allows a doctor to diagnose her, gets some medicine, and starts feeling much better within a week. After three months, she's fully recovered. The moral of this story is supposed to be to always take your antimalarials—but is it really, though?
An opposing moral is just to read up on the symptoms of malaria and pay attention to what your body is telling you. Know the difference between your body being biking-tired (or backpacking-tired) and malaria-tired, and if you suspect things aren't right, don't wait five or six weeks: go seek a doctor in the country you're currently in (all the better if that country is one that deals with malaria regularly). And, the story suggests, even if you do get malaria and don't get it promptly treated, chances are you'll have a bad month or two but emerge from it just fine in the long run. Cautionary tales can be scary, but they can also lack counterpoints. Here's a counterpoint: a man starts taking antimalarials before a trip to Ghana, and within just a week or two develops psychosis, thinks he's Jesus, and spends a month in a psychological hospital in Ghana (and another four in a psych unit back home in Holland).
I return to the hotel in which I’d spent the previous night to tell the staff that I won’t be checking out just yet. I’m clutching a small packet of multicoloured pills and instructions to rest throughout the three days of heavy medication I’ve been prescribed. I’m not planning to argue with this—after all, I’ve just learnt that the world’s single biggest killer has taken up residence in my bloodstream. I should be terrified. I have malaria, for goodness sake—the disease that kills one African child every forty-five seconds. So why do I feel so flippant? I have a bit of a fever, sorer-than-usual legs, a handful of pills, and a couple of days off to look forward to. What’s missing is any sense of the gravity of having being diagnosed with a potentially fatal disease. Why is that?
Here’s the thing. I have already accepted that what happens to me on this journey is mostly outside my control. I prepare for a balance between expected and unexpected. I’d taken anti-malarial drugs, for example. They hadn’t worked. I’d covered up and slept beneath mosquito nets: a couple of bites got through anyway. Bad luck. I’ve already dealt with so much in the way of unpredictability, of being exposed and vulnerable, on this journey that is rapidly proving the biggest test of my life. Learning precisely how little grasp I have over the way these elements of life play out, I long since stopped trying to fix the odds in my favour, or wasting energy on emotions like fear or frustration or anger which have absolutely no positive effect on the cards that have been dealt.
In summary: no prophylactics for us.
We'll do our best to not get bit, stay vigilant if we do, and get ourselves to a clinic if we start feeling any symptoms. I'd be surprised if we made it around the world without at least one of us getting malaria, so once that happens, we'll be sure to add an update here about our experience.
UPDATE (5/9/2017): Before leaving, we filled prescriptions for Doxycycline and Malarone, two antimalarials. Doxycycline also functions as a general-purpose antibiotic, and Malarone is actually a malaria treatment (if taken at a higher dose than prescribed as a preventative). We're bringing them as first aid in case we do get malaria, or in case Lauren changes her mind and wants to switch over to taking prophylactics just in case (I'm less likely to do so). Regardless of whether one's going to actually be ingesting them, bringing a supply along in the bottom of a pannier seems like a good idea no matter what.
UPDATE (1/13/2017): We've gotten a bunch of feedback on this post with varying degrees of support or opposition to skipping malaria pills. Most of the opposition is more emotional and less backed in any reason ("but malaria kills!"), though one really good counterargument to the thoughts above is that by not taking antimalarials (and later getting malaria), you're putting others (like the local population, and particularly its children, who may not have access to treatment), at risk of transmission. In short, this is the argument for the flu shot. It's a totally valid point and one that anyone else looking to not take prophylactics should balance with their own judgments and values (and again, this is not a post about what any of them should do; just what we, non-medical professionals, are planning to do). This ultimately doesn't change our decision, as there's a relatively low risk of becoming infected with other preventative measures, and also considering the fact that prophylactics can't always protect you from becoming infected and the reality that most members of the local population aren't taking prophylactics themselves and are sometimes being bitten hundreds of times per day. (Another comment pointed out that most prophylactics can't even be safely taken for long-term travel.) But it does present a wider perspective: this decision isn't just about us, but to a degree, those around us too. If you're weighing your own do-I-or-don't-I decision, take note.
Have you had any experience with malaria (or antimalarials)? How'd it go?