The UAE population is only 10 million (less than half of Karachi's), yet there has been an alarming rise in the number of Covid cases and even the US government has advised its nationals not to travel to that country. 

I believe there are many reasons for the spike. The first of course is the heavy use of air conditioners in the country. Most UAE nationals cannot survive without air conditioning. The few times they go to the beaches they breathe polluted and dusty air. Their main activity is going to shopping malls where the corona virus thrives due to the cold air circulating twenty four hours daily.

Another reason may be the lack of immunity of the people, who do not indulge in much physical activity (except when they walk towards their cars and get out of them). 

But perhaps the biggest reason is that the government has allowed foreigners to visit, ignoring the fact that airplanes are filled to capacity and the virus multiplies very easily. Even if the entire population of the country is vaccinated, Covid will continue to disrupt their lives.

It is ironical that the UAE has not been giving visas to nationals of underdeveloped countries like Pakistan, ostensibly because of concern that such people could bring the virus with them. The actual reason of course is that visitors from poor countries don't do much shopping and don't spend as much as those from richer countries. Let's hope the virus is conquered soon and the economy recovers.