Tap water is generally safe for drinking, though tourists are advised to buy bottled water for drinking. As a tropical country, Kerala is hot and humid so drink a lot of water.
Sanitation standards as well as personal hygiene among Malayalees are very high (http://www.kerala.gov.in/...). However most of the toilets do not have toilet paper option, hence it is advisable to carry a roll always. It is better to have bath atleast once a day, while in Kerala. This is because it is a social norm in addition to being a relief from the extreme humidity which makes a traveller sweat a lot. A bath atleast once twice is always betteris a true remedy for this problem.
Malaria is completely eradicated and not an issue, but dengue fever, cholera and viral fever is endemic to the region. Moonsoon time is considered as one of the major epidemic season, due to wet atmosphere, providing breeding ground for various water-borne virus. The state's mosquito control measures are not effective and mosquitoes still pose a major challenge. You require good mosquito controlling repellents which need to be applied regularly or use of mosquito coil or mosquito repellent mats etc at room as well as use of mosquito nets over bed. Various Kerala's spice extracts and oils prove an effective option to control mosquitoes.
While touring during summer days, its advised to always wear a cap or have an umbrella to avoid the harshness of the tropical sun. Also wear only cotton while touring during summer. Its also advised to drink Sharbath- a local popular road-side stall drink made of lemon juice mixed with sugar syrup with slight salt and mixed with soda. This helps to control dehydration a lot.
visiting religious centers
Kerala is one of the places where multiple religions exist in great harmony. This is achieved by one respecting the customs and rituals of other religions. A visit to these shrines is necessary to understand the breadth of cultural influences in the state.
In some Hindu temples non-Hindus are not allowed enter the shrines. It is best to ask someone at the temple. Many are happy to let you in as long as the usual rules of the temple are observed. However, photography inside the temple is a strict no-no.
Also for male visitors at many places inside a temple, dress code is traditional mundu without a shirt - the no-shirt rule will be enforced even if the mundu rule is not. The best thing to do is to watch what others are doing and follow. You are also expected to take off your footwear outside the temple. Usually there are no locker facilities, cheap footwear is best.
For females any non-exposed dress, preferably not shirts and trousers. Tidiness and personal hygiene is very important while entering into temples. A bath at morning is required for those entering into temple. Women who are in "menses", must refrain entering into temple for 7 days after the first sign of menses. Likewise its a ritual to refrain entering into temple, if any close maternal relative dies for a period of 16 days as a token of mourning. Same, in case of birth of any newborn which prohibits maternal relatives refraining from entering the temple for a period of 11 days since the birth of the newborn.
There are exceptions to these rules. For example everybody is welcome at Adhi Shankaracharya's temple. At Shabarimala any male that has performed a set of pre-defined rituals is welcome, but females are not.
At a Muslim mosque females have some restrictions. Some mosques do-not allow females inside and in those which allows, ladies must dress in absolute modesty. They must wear fully covering dress and cover their head with a shawl or scarf. No photography or any electronic equipments such as Ipods, FM players or Mobiles etc are allowed inside.
At Christian churches usually men sit to the left of the aisle and women to the right. Some of the more traditional churches don't even have pews...you'll have to stand. Ladies must cover their head with a shawl or scarf during the mass.
The synagogue at Kochi is not open to non-Jews on Saturdays. And on other days, visitors need to dress with modesty. Sleeveless tops, short trousers etc are not permitted to wear while visiting synagogue.
medical care
The standard of medical care in Kerala is excellent and this is a popular destination for medical tourism and medical research (http://www.keralamedicalt...). There are many leading hospitals, speciality centres, medical institutions of excellence, clinics, combined with large Ayurvedic hospitals as well as Siddha, Unani, Naturalopathy medical practices. Many hospitals in Kerala are of international standards and provide excellent medical care. Government run clinics and hospitals are free for all but can be crowded and not the best option for visitors. Private hospitals offer good treatment at comparatively low prices.
Government runs 4 types of medical care facilities
Primary Healthcare Centre PHC:- are the smallest unit in the hierarchy, which are spread over each nook and corner of the state. Kerala boasts the largest number of PHCs and provide general consultation facilities.
Taluk Hospitals TH/TC - located at headquarters of each taluk a smaller division in a district, which provides services of specialised doctors and also have in-patient block.
General Hospitals GH - GH are very common in most of the cities and towns and have larger premises, with super-specialty facilities. Many GH are also District Hospitals and houses a wide range of facilities. Normally its very crowded, due to free treatment and has very large In-patient block.
Medical College Hospitals MC - Kerala has 6 major large Medical college hospitals, which is very famous referral centres. All the medical college hospitals are well equipped and famed for complex surgeries and various major treatments. Medical colleges do have very large in-patient wards normally above 600 to 1000 beds, though nearly it caters 10 times more than its capacity. Trivandrum Medical College is the most famed medical which was rated as Medical centre of International excellence, equal to rank of All India Institute of Medical Sciences.
Both Govt and private operators also run Ayurvedic, Homeopathic and Naturalopathic community centres and clinics across Kerala.
For minor ailments, almost any private hospital or clinic found anywhere is good. Most of the private care hospitals are well equipped and have good physicians and specialists. Out-Patients are required to get appointment to avoid large ques and majority of them have pharmacies nearby.
Large super-specialty hospitals are available in major metros which are major research centres and famed for complex surgeries and treatments, thought its slightly expensive in Indian standards. Most of the hospitals in large towns and metros do accept foreign medical insurance cards, mainly issued in US, Europe and Middle East countries, apart from almost all national medical insurance covers, which needed to be check at hospital reception.
Kerala has some of the prestigious large Ayurvedic hospitals as well as super-specialty Ayurvedic Research centres, some even equipped to conduct surgeries and cancer treatments. Generally Ayurvedic healthcare centres are more expensive than Allopathic centres.