In your counterfactual example, we would have a much better warning coming from the third world. They would be hit much harder by the virus that affects the young disproportionately. We would literally see on TV millions of dead children in Third World countries perhaps even before the virus established a strong foothold. The beginning of the pandemic would look completely different. Isolating small children from any ways of getting in contact with the virus would become the highest priority until vaccines were developed. More different treatments would be tried. Small children would become treated as immune compromised bubble boys. They would be living in a bubble.
In your counterfactual example, we would have a much better warning coming from the third world. They would be hit much harder by the virus that affects the young disproportionately. We would literally see on TV millions of dead children in Third World countries perhaps even before the virus established a strong foothold. The beginning of the pandemic would look completely different. Isolating small children from any ways of getting in contact with the virus would become the highest priority until vaccines were developed. More different treatments would be tried. Small children would become treated as immune compromised bubble boys. They would be living in a bubble.