niki......everything that everyone is writing is true...pregnancy, menopause, stopping smoking, etc etc all put on weight...but none of that for the future helps you right now where you are if you really want to gain a little weight..and if you do feel weak after the malaria... although dear the weakness may not be due to the thinness.. or weight loss...but...that said..everyone's metabolism is different so what works for one won't work for another....
some healthy suggestions to try to see IF they work for you are to eat healthy fats and healthy protein. Healthy fats are coconut oil, (to cook in) flaxseed oil and olive oil for salads, some ghee and/or butter. Bad fats are corn oil, canola oil. Snack on nuts, not just almonds, but cashews and other nuts too, and popcorn with butter. Cook the popcorn in coconut oil. Eat vegetables like avocado, lentils, and beans. Drink milkshakes, protein shakes. Eat healthy protein like salmon, sardines, herring and eggs. All of these i have mentioned are very healthy for you and will NOT raise cholesterol for later in life. Actually, bad fats and sugar is what raises the cholesterol and does lots of damage...so if you must have sweets limit the sugar and eat honey or coconut sweetened things...
good luck !! and hope you get your pierced ears to wear some cute earrings !!!