Disease may be underreported due to lack of funds to pay medical staff to diagnose and report disease, as in the USA. Sometimes political and religious concerns hinder accurate reporting of disease, as for example, with a Nigerian outbreak of meningitis at the time of the haj. The Saudi authorities in Mecca wished to turn away Nigerians for fear of their spreading meningitis among the pilgrims to Mecca, so the Nigerians underreported the scale of the epidemic.
In certain cultures, epidemic diseases are seen as moral plagues sent to punish sinners, and so victims do not report their disease for fear of social stigma.