Food by definition is any substance either flora or fauna that when consumed provides nutritional support for the body in an effort to produce energy, maintain life, or stimulate growth. It contains nutrients inevitable for life, such as fats, carbohydrates, proteins, minerals, or vitamins. Since ancient times, people secured food through two methods – hunting and stocking – that are still being practiced. Today, food industry has become the most inevitable industry feeding more than seven billion people.
Legitimacy of food industry in Pakistan has become questionable since the past few decades which might be associated with the increasing trend of urbanization. There is a set of four laws that specifically deals with food safety. Three of them directly focus the issues related to food safety, while the fourth namely, the Pakistan Standards and Quality Control Authority Act, is indirectly involved.
Food-borne infectious diseases are well recognized and are becoming more common in human beings. Predominantly bacterial, fungal and viral infections have been linked with the food-borne infections, while parasitic infections have received less attention. The significance of parasitic food-borne diseases is generally under-recognized in the developing world which might be due to inadequate systems of diagnosis, monitoring and or reporting. Factors that may explain the emergence of some zoonotic parasitic diseases are: (a) international marketing of food, (b) increased frequency of travel, (c) increased population of susceptible hosts because of aging, malnutrition, infection and other underlying medical conditions, (d) changes in life style, such as the increase in the number of people eating foods available in restaurants, hotels and famous fast food icons as well as from street food sellers who do not always respect food safety.
Amid many developing countries, (a) inappropriate sewage system, (b) practice of watering the vegetables with sewage water and (c) draining of sewage water in the canals, rivers and seas, have increased the frequency of parasitic infections transmissible through fecal contamination of food stuff. It is often difficult to associate an outbreak with a particular food item. The predominant modes of transmission of parasitic diseases include: water, meat, milk, eggs and vegetables contaminated with sewage water have been comprehensively discussed below.
Among emerging water-borne parasitic infections that may be acquired by food include infections of Cyclospora spp., Giardia spp., Cryptosporidium, Fasciola, Fasciolopsis, Echinococcus (E.) granulosus, and E. multilocularis. Infective stages of these parasites shed in the environment with feces of infected animals, can contaminate food stuffs such as vegetables, fruits and fruit juices. Of particular concern in industrialized countries are water-borne protozoa infections, which are difficult to control, given their high level of resistance to environmental conditions.
Milk is a complete diet for all age groups; however, major portion of milk is consumed by infants and growing age children. So, milk-born parasitic problems are of significant health and food safety issue for young age group. In milk-borne parasites infections mainly include Enterobious spp., Toxoplasma gondii and T. solium. Vertical transmission of Ascaridia galli in the eggs is an alarming situation for the egg consumers with special reference to those body builders in rural areas using raw eggs as a source of protein.
There are some serious issues facing developing countries including: (a) little customer understanding of food safety issues, (b) fragmented industry, (c) small and unorganized sector possessing a major number of food processing units, (d) unskilled food handlers, (e) diversity of food products, (f) inadequate laboratory testing infrastructure and conventional practices of storage and carrying of food etc.
Culinary habits of primarily the sea foods in countries other than India and Pakistan play a major role in the exposure to these zoonotic parasites to human population. Particularly, Chinese raw sea foods have been reported to be an important source of zoonotic infections in humans. The increasing demand for food, particularly in the developing countries like Pakistan will lead to an increase of livestock, agriculture products, poultry and fish production and an intensification of the production systems. With the passage of time, the rise in general public concern over security of the food chain and food safety has helped to focus more attention on zoonotic parasites.
Monitoring and control of food-borne parasites can be done using modern risk assessment tools including: (a) monitoring of water and food utilizing new technologies e.g. serological and molecular approaches, (b) health education, (c) social and economic development, and (d) proper deworming, vaccination and prophylactic mass treatment of food animals.
Followings are some golden rules proposed by the WHO for the prevention of food-borne zoonosis at the consumer’s level: (a) adequate food processing, (b) proper cooking (c) eating fresh food, (d) proper storage (e) thorough reheating, (f) no contact between raw & cooked food, (g) washing hands before eating, (h) cleanliness of food preparation surfaces, (i) protection of food from pests, and (j) using potable water for cooking and washing of food stuff. Implementation of these rules in the developing countries at the consumer’s end is the need of hour. However, the policy makers may prioritize the agenda to include: (a) health awareness campaign about food procurement and processing by the consumers, (b) encouragement of cultivation of transgenic crops and food animals biologically resistant to parasitic and other infections, (c) provision of treated water with hazard free chemical to farmers for irrigation of crops, vegetables and fruits. In addition, 95 per cent of our population is still deprived of pure drinking water which needs to be highlighted and ensured to reduce major food-borne infectious threats to the nation.