[openforce]

Diseases transmitted by mosquitos have increased tremendously in the last decade, Especially in developing nations. I am from India and we never used to hear about cases of Dengue or Chikungunya 10-15 years ago. Now its all too common. Looks like this is a similar disease, now with links to microcephaly. Dramatic increase in city populations, poor infrastructure result in increased mosquito breeding grounds These nations need to heavily invest in taking out disease carrying mosquitoes or situations like these are only going to increase.

[bayesianhorse]

I sometimes wonder how much of "we never heard of x/y/z disease 10-15 years ago" is due to less frequent testing.

[openforce]

Significant number, maybe. Penetration of medical services in these countries has increased quite a lot in the same time span. But, impact of this depends on the type of disease.

Significant increase in breast cancer cases for example is I believe a direct result of increased diagnosis. But, for the increase in cases of viral diseases, I believe the majority cause is due to things like more dense population, unsanitary conditions and poor infrastructure.

[bayesianhorse]

I'd exclude breast cancer because it's detectable with non-medical means before it becomes fatal. I also wasn't speaking so much about medical incidence statistics, but more about perceptions.

[ufo]

Diseases like this are something that forces you go to the doctor, where its gonna gain a diagnosis. With diseases like Zika and Chikungunya the big problem is globalization and air travel.

[bayesianhorse]

How is a doctor supposed to diagnose a Virus like Zika without advanced lab tests? The symptoms are non-specific and often non-obvious. In fact, I doubt Zika virus was regularly tested for.

[blowski]

Also, social media and the 24 hour rolling news cycle give a lot more coverage than 20th Century TV news bulletins and newspapers.

[dalke]

How do you know that's true about Dengue? http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3510884/ (from Indian J Med Res. 2012 Sep; 136(3): 373–390. ) says:

> The epidemiology of dengue fevers in the Indian subcontinent has been very complex and has substantially changed over almost past six decades in terms of prevalent strains, affected geographical locations and severity of disease. The very first report of existence of dengue fevers in India was way back in 1946[15]. Thereafter, for the next 18 years, there was no significant dengue activity reported anywhere in the country. In 1963-1964, an initial epidemic of dengue fever was reported on the Eastern Coast of India[7,16–20], it spread northwards and reached Delhi in 1967[21] and Kanpur in 1968

then continues with many more recent epidemics of Dengue in India throughout the decades.

I can think of several other hypotheses, besides a rise in mosquito-transmitted diseases, which can fit your observation:

1) you didn't pay attention to it 15-20 years ago, or your memory has faded, 2) other diseases, like polio and malaria, were more significant so played a larger role in health reporting, 3) people and news sources talk more about health issues now than then, 4) official counts which were deliberately under-stated are now becoming more realistic.