Hello,
Yes prickly heat or malaria can last for months.It is common for milaria to occur when people travel to a warmer climate and sweat more than usual. In most cases the rash will clear without any treatment. However, severe cases can last for several weeks to months.
I hope it helps.Take care and pls do keep me posted on how you are doing or if you have any additional doubts.Kind regards.
id like to know the answer to that also because ever since i moved to a hotter climate iv had a rash on chest and back and i think its prickly heat rash because i sweat alot more now but iv had it for almost a year!!!