Z&M, as to your first statements and question, I have indeed wondered over certain seemingly disparate dollops of information for years; but I have finally, and tentatively, concluded that there are degrees of - not always absolute - advice when it comes to malaria. The reason for this is that people are also weighing up the risk of an individual contracting malaria in a risk area versus the benefits of going there in the first place.
The finest advice would be to completely ensure that a young child does not enter a malarial area at all, because, as has been mentioned previously, and as examples: (i) their immune systems may not yet be fully developed and so progression of the disease may be fatal quicker; (ii) it is not always easy to effectively and timeously diagnose malaria in a young child (they may not be able to effectively communicate their symptoms and how they're feeling; they may have other concurrent conditions/diseases whose symptoms and signs may approximate that of malaria; they, or their signs and symptoms, may only alert the parent to visit a doctor at a too-late stage; and so on); (iii) it may be more difficult to impress upon a child the need to stay indoors after dark and "hamstring" themselves with seemingly annoying non-drug measures.
Many parents feel the need to weigh up the options at their disposal and determine whether they will take the risk - however small or large - of exposing their children (and themselves) in a malarial area. I personally did not take my daughter to a malarial area until she was 8 years old as I know the dangers and was unwilling to expose her to them. Other parents will totally disagree with me. Each to his/her own.
Most official recommendations will suggest not taking children less than five years old to a malarial area - both high- and low-risk areas - as this is generally the best advice for them (as explained earlier). However, in the event that the child still goes to a malarial area (and particularly a high-risk one), then there are antimalarial drug options available to minimise that child's risk of contracting the disease. Not a perfect situation by any means, but at least the risk will be lowered. Of course, with medications comes potential side-effects that may hamper the child and/or cause serious distress. Again, these need to be considered in the final decision.
There are many factors to take into account to decide whether a young child (and of course any individual) is to enter a malarial area, but the bottom line is that as long as there is risk of contracting malaria, the person involved will be exposed to that risk, to a lesser or greater degree depending on what precautions are implemented to lower the risk.
Now, more specifically to you, Z&M, my recommendation for your 4-year-old is still the same; avoid malarial areas if you can. If you choose to take your child anyway, be very diligent in applying non-drug measures from just before sunset until just after sunrise. I would also consider adding antimalarial drugs (especially in high-risk season), but do this in conjunction with a well-recommended medical practitioner experienced in malaria prevention and treatment. Is it worth giving the drugs, you ask? Antimalarial drugs suitable for that patient, and given correctly and regularly, will almost certainly reduce the chances of the patient contracting and/or dying of malaria. However, this does not mean that the person will be fully protected, and hence the need still for non-drug measures with the antimalarial medication. And monitor the child for at least six weeks [and, more wisely, up to three (and some sites suggest six) months] after first entering the malarial area for any signs or symptoms that may indicate a malarial infection. If in doubt, check with a medical doctor!
Disclaimer: My recommendations here - though based on some experience and some drug, and other, knowledge - are not absolute, and further consultation with suitable health-care professionals is suggested before a final decision is taken on whether to enter a malarial area, what prophylaxis to use, and any general factors and limitations that need to be taken into account. Furthermore, I only advise based on what information is given by the person(s) entering the malarial area, but I have no control on the information given to me, and so such information could possibly be incomplete or misleading. Moreover, people vary subjectively as to how they metabolise, and react to, drugs and other substances, which further accentuates that my suggestions here are only general suggestions, and therefore not to be taken as pertaining to every person alike.
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