Food can kill you: handle and conserve food properly

According to the World Health Organization (WHO), it is estimated that every year around 600 million people get sick around the world, almost 1 in 10 people, from eating contaminated food, and 420,000 die. Recently there have been different cases of food poisoning in Spain.

On the one hand, we’ve seen the largest outbreak of listeria in our country. It is one of the most dangerous pathogens since it withstands lack of oxygen and freezing temperatures. It has a mortality rate between 20 to 30%.  Another important outbreak has been the presence of botulinum toxin in canned tuna conserved in DIA brand sunflower oil. These outbreaks have occurred in such a short amount of time that it is important to take precautions and understand the seriousness of the situation.

Tania Mesa – Director of Neolife’s Nutrition and Nursing Unit

Alejandro Monzó – Neolife Nutrition and Nursing Unit

More than 200 known diseases are transmitted through food

Foodborne diseases (FBD) constitute a major cause of morbidity and mortality and a significant impediment to socio-economic development worldwide. The report “Estimating the global burden of foodborne diseases” published in 2015 by the WHO is the first to offer complete estimates of the disease burden caused by 31 pollutants (bacteria, viruses, parasites, toxins and chemicals) globally and regionally (1,2).

This report shows that in 2010 these 31 agents caused 600 million cases of FBD’s and 420,000 deaths. The most frequent causes of FBD were the etiologic agents of diarrheal diseases particularly norovirus and Campylobacter spp. The global burden of FBD is considerable, but it varies greatly by region and affects people of all ages, especially those under 5 and those living in sub-regions of the world with low incomes (2).

Food contamination can occur at any stage of the manufacturing or distribution process (Figure 1.), although the responsibility lies primarily with the producer. However, many foodborne illnesses are caused by foods that have been improperly prepared or handled at home, in establishments serving food or in markets.

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Figure 1. The main routes of transmission of FBD in humans: reservoir level and exposure level (2).

Improper food handling poses threats to health and endangers the lives of all, especially the most vulnerable, such as infants, young children, pregnant women, the elderly and people with underlying diseases. Unclean foods generate a vicious cycle of diarrhea and malnutrition that compromises nutritional status with the health consequences that this entails. When the food supply is unsafe, people tend to adopt less healthy diets and consume more “unhealthy foods” that contain chemicals, microorganisms (also called microbes) and other health hazards (1,2,3) .

FBD’s are generallyinfectious or toxic and are caused by bacteria, viruses, parasites or chemical substances that penetrate the body through contaminated water or food (1). These agents can cause severe diarrhea or debilitating infections, such as meningitis, long-term illnesses, such as cancer or even persistent disability and death. Therefore, some examples of unsafe foods are uncooked foods of animal origin, fruits and vegetables contaminated with feces and raw shellfish that contain marine biotoxins (1,4).

Therefore, clean food control, nutrition and food safety are closely related. Below, we list the main etiologic agents of foodborne diseases presented by the WHO (1,2,5):


Salmonella, Campylobacter and Escherichia Coli are among the most common pathogens. Their symptoms are fever, headaches, nausea, vomiting, abdominal pain and diarrhea. The foods associated with salmonellosis are eggs, poultry and other animal products.

Cases of Campylobacter infection are mainly due to the ingestion of raw milk, raw or undercooked poultry and drinking water.

E. Coli is associated with the consumption of undercooked meat, unpasteurized milk, fresh fruit and vegetables.


The characteristic symptoms are nausea, vomiting, watery diarrhea and abdominal pain. The Hepatitis A virus can cause persistent liver diseases and is transmitted by ingestion of raw or undercooked shellfish or contaminated raw products. Food handling by infected people is usually the source of contamination.


Some parasites, such as trematodes present in fish, are only transmitted through food. Others, such as Echinococcus spp or Taenia solium can infect people through food or through direct contact with animals.

Chemical products and toxins

For example, aflatoxin is produced by a mold that grows in improperly stored grain and can cause liver cancer. Cyanide may be present in cassava (mandioca/yuca) that is improperly processed.

Our country follows strict rules of the European Union and its work has been endorsed by the U.S. Food and Drug Administration (FDA). Safety levels are higher than ever and have improved significantly in recent decades, reducing the number of episodes and their mortality. However, zero risk does not exist (6). There are very strict rules and controls, but there are producers and companies that do not comply with them.

The Spanish Agency for Consumer Affairs, Food Safety and Nutrition (AECOSAN) activated a health alert for an outbreak of food poisoning caused by botulinum toxin detected in canned tuna conserved in DIA brand sunflower oil after knowing that four people had become ill (7). Botulinum toxin is a neurotoxin created by a bacterium called Clostridium botulinum. The ingestion of food contaminated by this toxin causes botulism, a disease characterized by the development of vegetative alterations, such as dry mouth, nausea, vomiting and progressive muscular paralysis (8).

Recently, in Andalusia, there was an outbreak of food poisoning caused by the listeria bacteria associated with the consumption of ground beef, and there have already been more than 200 cases throughout the country. Listeriosis is an infection caused by the bacterium Listeria monocytogenes, a disease that is usually serious with high rates of hospitalization and mortality (9). In infected people the symptoms vary, from mild flu-like symptoms, to more serious infections, such as meningitis, septicemia and pneumonia. The elderly, pregnant women, newborns and immunosuppressed people are the most susceptible.

Since zero risk does not exist, in order to protect human health and manage food risks to the health of consumers, a coordinated system of food alerts is in place. These networks allow constant monitoring of any risk or incidence related to food (10). For AECOSAN, the primary basis is the rapid exchange of information between the different competent authorities, food companies and consumers, thus facilitating timely actions on those food products that could have an impact on the health of consumers.

It is worth remembering other food crises in Spain, such as adulterated rapeseed oil almost 40 years ago, the chickens of the Sada Group contaminated with salmonella in 2005, the crisis of Spanish cucumbers in 2011, bird flu or the mad cow crisis. These cases have marked a before and after when it comes to sanitary controls.

At Neolife, we want to express the importance of proper food handling, proper hygiene and finally, disease prevention to protect our health. Although zero risk does not exist, it is possible that new food alerts may appear again, so we always have to keep in mind the following recommendations for food safety provided by the WHO (3):

  • Wash your hands before beginning food preparation and often while handling them. Also wash your hands after using the bathroom.
  • Wash and disinfect surfaces and utensils that you have used after food preparation.
  • Protect food and food preparation areas from insects, rodents and animals (dogs, cats, etc.).
  • Store and keep raw and cooked foods separate, both in the kitchen, in the pantry and cupboards, and in the fridge.
  • Use separate utensils for raw and cooked foods or wash them before reuse.
  • Prepare food making sure it is fully cooked (exceeding 70 degrees in its center), especially eggs, chicken, meat and fish. Fully reheat food cooking to at least 70 degrees.
  • Do not leave food at room temperature for more than 2 hours. Put them in the fridge immediately after preparation if they are not going to be consumed immediately.
  • Do not store food for a long time. Respect the guarantees of preservation of frozen foods indicated by the label or your freezer. Do not defrost food at room temperature. Do it in the fridge.
  • Buy food at authorized establishments, with labeling and checking expiration dates.
  • Read carefully and maintain the conservation requirements and expiration dates of food.


(1) (2019). “Food safety: key facts”. World Health Organization.


(2) WHO. (2015). “WHO estimates of the global burden of foodborne diseases”. World Health Organization.


(3) WHO. (2007). “Manual sobre las cinco claves para la inocuidad de los alimentos”. Biblioteca de la OMS.


(4) Junta de Andalucía. (2010). “Manipulación de alimentos: manual común”.



(5) (2015). “Principales agentes etiológicos de las enfermedades de transmisión alimentaria”. Carga Mundial de Enfermedades de Transmisión Alimentaria: estimaciones de la OMS.


(6) Stegmann, J.G. (2019). “España, un ejemplo para el mundo en seguridad alimentaria. Diario ABC, sección sociedad.


(7) (2019). “Brote de intoxicación alimentaria causado por toxina botulínica asociado al consumo de conserva de atún en aceite de girasol”. Ministerio de sanidad, consumo y bienestar social, España.



(8) (2018). “Botulism”. U.S. National Library of Medicine.


(9) (2019). “Actualización de información sobre el brote de intoxicación alimentaria causado por Listeria monocytogenes”. Ministerio de sanidad, consumo y bienestar social, España.



(10) (2019). “Red de alerta alimentaria”. Ministerio de sanidad, consumo y bienestar social, España.