Are there any risks which may become increasingly acute as the time since a disaster evolves?
The length of time that people spend in temporary settlements is an important determinant of the risk of disease transmission which might lead to major epidemics. The prolonged mass settlement of in temporary shelters with only minimal provision for essential personal hygiene is typical of a situation that may cause epidemic outbreaks of infectious diseases.
The main risks of epidemics come from unsanitary conditions and can include, for example, typhoid, dysentery, cholera, and diarrohea. Leptospirosis may also be transmitted through contaminated water or food stuffs that have been contaminated by the urine of infected rats or other animals. Diseases related to overcrowded conditions such as respiratory infections, typhus, and infestations from scabies and lice are also of concern. Diseases spread through mosquito vectors such as malaria, dengue, and Japanese encephalitis may also arise when disease vectors are allowed to breed in stagnant water or even standing water in old tires, cans, etc. Communities may be especially vulnerable to vector-borne diseases when they are living without shelter or access to bed nets.