Hi,
It is almost impossible to get intestinal myiais by consumption of a fly egg because the human immunity is too strong and mounts a resistance to such infection. As you rightly mentioned, the stomach acidity of pH of 2 destroys and denatures the proteins present in the egg.
Myiasis is the infestation of live humans and other vertebrate animals with larvae which, at least for a certain period, feed on the host's dead or living tissue, liquid body substances, or ingested food. In urban areas of developed countries cases of intestinal myiasis are rare and most have occurred in countries where nutritional and sanitary conditions are unsatisfactory.
They present as diarrhea, fever, muscle ache, headache, and abdominal pain with tenderness.
I would also recommend that you eat a good balanced diet with good portion of proteins carbohydrates and vitamins. Consume diet rich in green leafy vegetables and milk. This will help in improving the immunity of the body.
Thank you.