It is highly unusual to be allergic to every class of antibiotics on the market, so I would wonder what classes you are indeed allergic to - the most common are penicillin and sulphonamides. Also, when you say you're allergic, what actually happens? In other words, do you swell up and have to be rushed to hospital, or is it just gastrointestinal discomfort or vomiting?
Remember that antibiotics are designed to kill the bacteria in one's system and do not kill human cells; the side-effects are a result of disturbances to human systems, such as an imbalance of "good bacteria" in the gut. Malarone (atovaquone with proguanil) also attacks foreign organisms, not human cells: it works by interfering with the growth of parasites in the red blood cells of the human body. Perhaps in that way it is similar, although it is a schizonticide and not an antibiotic.
Technically speaking, the beginning of October defines the boundary between low and high risk areas in seasonal malarial areas in South Africa. Therefore, October to May is considered high risk in Kruger and both the World Health Organisation and the South African Department of Health recommend the use of antimalarial tablets in addition to non-drug measures (antimalarial sprays, netting, citronella-oil products, long sleeves and trousers, etc.).
I say technically because there are other factors that affect the proliferation of mosquitoes, most especially the advent of the rainy season. If it is still dry and there is an obvious dearth of mosquitoes when I go to Kruger at the beginning of October, or the end of May, I tend to not use antimalarial tablets - although I always indulge in non-drug measures - but that is only what I do, and is not necessarily a recommendation for others, especially as the official guidelines state otherwise.
Ultimately, you need to decide what you want to do regarding taking antimalarial tablets or not. It depends on various personal factors too, which only you can consider and weigh up.
As to staying outside Kruger and doing day-trips in, I agree wholeheartedly with the others. I did it only once and I will not do it again in a great hurry! Stay in Kruger if you can - you will not be sorry from a game-viewing experience.
Though it is true that mosquitoes do not honour human geographical boundaries, one must remember that certain areas outside Kruger may not be diligent enough in spraying and controlling their mosquito populations on a regular basis. Kruger is indeed diligent (as far as I know) and most of their accommodation, in my experience, has netting, although some of the older accommodation may have not had the netting sufficiently repaired to prevent mosquitoes squeezing through. Nevertheless, I have seldom had problems with mosquitoes inside the accommodation - mostly, I get bitten outside between dusk and dawn - and, in summer, I further restrict mosquito access within units by keeping the air conditioning on.
There are indeed some places outside Kruger that are all-year-round low risk - such as Hazyview and Hoedspruit - but my choice, if I had yours, would still be to stay in Kruger and take suitable and sensible precautions against malaria infection. Remember that a low-risk does not mean no risk, although it IS lower than a high risk area.
Whatever you do, dcbee, enjoy your trip to the full!
Disclaimer: My recommendations here - though based on some experience and some drug 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.
_________________EVERYBODY'S TR!TR: A NEW DAY IS S-OWNTR: NECTAREAN NICETIES OF THE NORTHTR: PRIMEVAL PLEASURE"Outside of a dog, a book is a man's best friend. Inside of a dog, it's too dark to read." (Groucho Marx)