by Reborn » Mon Dec 10, 2018 9:38 am
> But if no westerners are on the island, how do we know about their immunities (or is it only guessing)?
We don't know that based on having them tested, no. We can however conclude it based on two general sources.
1. Historical records - while the Sentinelese are considered uncontacted for the most part, it is not that they haven't come into contact at least a handful of times throughout history. On one occasion, during the colonial times a group of them was captured. Two adults and four children that were brought inland. Nearly immediately they all became ill and the adults died. The children were then promptly returned to the island. Whether they were accepted back is unknown. If they did, perhaps the Sentinelese went through some sort of pandemic and the survivors gained immunity for that particular disease, but that's only my speculation.
2. Knowledge and common sense on how disease spreads. You can't have a disease unless you managed to come in contact with it. While there are some vectors of transmission through animals that could reach the island, others can't. Think historically. Even within a country or a continent diseases spread gradually like the bubonic plague as an extreme example. While we didn't have immunity for that, things like cold spread similarly. They also evolve. When we reached the colonial times in Europe, we already had large towns and with the lack of proper hygiene and more contact between each other diseases spread and mutated quicker, had more opportunities to form. That also meant for some we developed immunity.
When we went to the Americas, we also brought diseases the native people had never experienced and therefore never developed an immunity for. Even something as simple as common cold could have had strains more mutated and aggressive than what they had. Since their living conditions were different than ours, they didn't have as many diseases that would pose threat to the Old World colonists. Same goes for uncontacted tribes that humans have met in other parts of the world afterwards. The story repeated itself over and over. The outside world meets uncontacted people and people got sick. Some even recently to have been able to study and figure it out.
Other than a handful of contacts, these people had been pretty secluded for roughly 60K years. It is reasonable and nearly certain they have no immunity to modern diseases.