You got water problems? These are water problems: Food production in arid regions

Climate change is one of the major challenges of our time that pose unprecedented stress to the environment and threats to human health. The global impacts of climate change are vast, spanning from extreme weather events to changes in patterns and distribution of infectious diseases.

Lack of rainfall associated with higher temperatures has a direct influence on agricultural production. This is compounded by a growing population forecasted to expand further with increasing needs for food and water. All this has led to the increasing use of wastewater worldwide.

In this review, we more specifically discuss the use of untreated wastewater in agriculture in the Middle East and North Africa (MENA) countries, the most arid region in the world. This presents challenges for agriculture with respect to water availability and increasing wastewater use in agri-food chain. This in turn exerts pressures on the safety of food raised from such irrigated crops.

Current practices in the MENA region indicate that ineffective water resource management, lack of water quality policies, and slow-paced wastewater management strategies continue to contribute to a decline in water resources and an increased unplanned use of black and graywater in agriculture. Radical actions are needed in the region to improve water and wastewater management to adapt to these impacts.

In this regard, the 2006 WHO guidelines for the use of wastewater contain recommendations for the most effective solutions. They provide a step-by-step guide for series of appropriate health protection measures for microbial reduction targets of 6 log units for viral, bacterial, and protozoan pathogens, but these need to be combined with new varieties of crops that are drought and pest resistant. More research into economic local treatment procedures for wastewater in the region is warranted.

The Impact of Climate Change on Raw and Untreated Wastewater Use for Agriculture, Especially in Arid Regions: A Review


Foodborne Pathogens and Disease, Volume 15, No. 2

Faour-Klingbeil Dima  and Todd Ewen C.D.


Salmonella increases in warmer Adelaide weather

Changing trends in foodborne disease are influenced by many factors, including temperature.

adelaide.Globally and in Australia, warmer ambient temperatures are projected to rise if climate change continues. Salmonella spp. are a temperature-sensitive pathogen and rising temperature can have a substantial effect on disease burden affecting human health. We examined the relationship between temperature and Salmonella spp. and serotype notifications in Adelaide, Australia.

Time-series Poisson regression models were fit to estimate the effect of temperature during warmer months on Salmonella spp. and serotype cases notified from 1990 to 2012. Long-term trends, seasonality, autocorrelation and lagged effects were included in the statistical models. Daily Salmonella spp. counts increased by 1·3% [incidence rate ratio (IRR) 1·013, 95% confidence interval (CI) 1·008–1·019] per 1 °C rise in temperature in the warm season with greater increases observed in specific serotype and phage-type cases ranging from 3·4% (IRR 1·034, 95% CI 1·008–1·061) to 4·4% (IRR 1·044, 95% CI 1·024–1·064).

We observed increased cases of S. Typhimurium PT9 and S. Typhimurium PT108 notifications above a threshold of 39 °C. This study has identified the impact of warm season temperature on different Salmonella spp. strains and confirms higher temperature has a greater effect on phage-type notifications. The findings will contribute targeted information for public health policy interventions, including food safety programmes during warmer weather.

The effect of temperature on different Salmonella serotypes during warm seasons in a Mediterranean climate city, Adelaide, Australia

Milazzo, L. C. Giles, Y. Zhang, A. P. Koehler, J. E. Hiller and P. Bi

Epidemiology and Infection, 144, pp 1231-1240


Climate change responsible for increase in vibriosis?

Rob Mancini writes:

My wife and I decided to visit France and spend some time with her lovely relatives. We were treated like gold, they really like Canadians.  The scenery, the wine, cheese and the company was unsurpassed. As a treat one evening we caught some fresh oysters, shucked them, and ate them with a dash of lemon juice. This was followed with some great beer and local wine. I have oysternever been a fan of oysters because of the slimy texture and the risk of Vibrio spp. but had to try it and none of us became ill. A couple vacationing in Panama City wasn’t as lucky. The Huffington Post reports :

Forty-year-old Darrell Dishon wasn’t an oyster fan. Before June of 2009, he’d never even tried one. So when his wife Nicole proposed splitting a dozen raw shellfish at a restaurant in Panama City, Fla., where the two were vacationing, he was leery.

Nicole remembers eating 10. She says Darrell ate two.

The doctors delivered the awful news that he had contracted a form of vibriosis, one of the most deadly foodborne illnesses in the world. Over the following weeks, Darrell’s health continued to decline. He developed life-threatening septicemia. His doctors amputated both his legs above the knee in an effort to stop the spread. In December, Darrell Dishon became one of the approximately 15 people each year who succumb to vibriosis after eating raw oysters. Vibriosis is an incredibly rare disease — but Centers for Disease Control and Prevention data show that it’s getting more common.

“While all the other pathogens have shown a nice decline, the vibrios are about twice what it was since 1998. In a little over a decade, incidence has doubled. They’re still relatively small numbers — but it’s a very striking increase,” leading vibrio researcher Glenn Morris of the University of Florida’s Emerging Pathogens Institute told The Huffington Post.

Vibrio thrive in warm water. One widely publicized study published in July 2012 indicated that a 1-degree increase in the temperature of a body of water triples its vibrio population. For that reason, many scientists believe that climate change has contributed to the recent rise in vibriosis, and that it could make vibrio bacteria much more prevalent in coming years.

The culprit was Vibrio vulnificans, a bacterium in the same family as those that cause cholera. The bacterium causes fever, diarrhea, abdominal cramps, nausea, and vomiting, and often death. Cook shellfish thoroughly (63°C; 145°F) to avoid infection.