Dear Mosab. Thank you for your question. We have only four blood groups as variables and we know from several studies that the frequency of ABO groups and Rhesus D blood group vary from one population to another. Therefore, in order to receive an evidence-based study, you need the authors in their method to include several countries (3-4 different countries) with a good number of participants, and if such association is found, the result might be considered an observation that need to be confirmed by other researchers. I hope this helps. Best regards.

thanks dear Samy,

I am not been sure about this possible correlation

I read that information in certain journals I think it may be parasitology today , but I need explanation .

Maybe the following papers will help you:

1. el Naggar B, Gaafar S, Shoman A.Relationship between Giardia lamblia infection and blood grouping among children. J Egypt Soc Parasitol. 1984 Jun;14(1):155-8.

2. Giboda M, Bernasovský I.Giardiasis and ABO blood groups. J Hyg Epidemiol Microbiol Immunol. 1983;27(4):461-4.

3. Abdurahaman Seid , Zemenu Tamir, Brhanu Kasanew and Moges Senbetay .Co-infection of intestinal parasites and Helicobacter pylori among upper gastrointestinal symptomatic adult patients attending Mekanesalem Hospital, northeast Ethiopia . BMC Res Notes (2018) 11:144

Maybe the following papers will help you:

1. el Naggar B, Gaafar S, Shoman A.Relationship between Giardia lamblia infection and blood grouping among children. J Egypt Soc Parasitol. 1984 Jun;14(1):155-8.

2. Giboda M, Bernasovský I.Giardiasis and ABO blood groups. J Hyg Epidemiol Microbiol Immunol. 1983;27(4):461-4.

3. Abdurahaman Seid , Zemenu Tamir, Brhanu Kasanew and Moges Senbetay .Co-infection of intestinal parasites and Helicobacter pylori among upper gastrointestinal symptomatic adult patients attending Mekanesalem Hospital, northeast Ethiopia . BMC Res Notes (2018) 11:144

thanks dear