Medical waste is a serious threat in all developing countries, although it may not be as big a threat as reused contaminated equipment and other unsafe practices in health facilities. Thousands of people scrape a living from dumping sites by trawling for things that can be sold or reused. But if healthcare waste is not being dumped properly, they can come into contact with scalpels, needles, syringes, glass and other items.
The article above mentions the unlicenced clinics that are so common around all slums in Nairobi. But there is no mention of reuse of medical instruments. Perhaps it never happens, but even in legitimate health facilities, some healthcare workers seem to assume that safety precautions are to protect them from accidential exposure to pathogens, not their patients.
I've been to several health facilities in Kenya, Tanzania and Uganda and it is fairly obvious that some of the waste never makes it to dumps. It is not unusual to find used equipment on grassy areas, in bushes and in various places on the hospital grounds. I've even seen kids playing with clinical waste.
According to the article, backstreet clinics in Nairobi alone are being closed down at a rate of more than 15 a month. I'd be curious to get an idea of what kind of conditions are found in such clinics but I haven't seen any reports. While those sifting through rubbish face some risk, patients may face even higher risk of illegal clinics are unaware of or not compliant with infection control procedures.
The article cites an estimate from the British Health Protection Agency that up to 1 in 300 people could be infected with HIV through contact with contaminated medical waste. But if that's the case in the UK, where HIV prevalence is very low, the risk must be far higher in Nairobi, where prevalence is nearly the highest in the country. The risk of hepatitis and other blood borne diseases is even higher still.
If reports of conditions in Kenyan hospitals are true, unhygienic conditions in dump sites must be the least of their worries when it comes to accidental infection with HIV and other blood borne diseases.