Public Health Threat with Consumption of Unpasteurized Milk: Systematic Review

Unpasteurized milk consumption is common throughout the globe, despite the negative consequence for consumer health. This review paper identi�ed public health risks resulting from unpasteurized milk. Several keywords were used to search online, including Google Scholar, PubMed, Science Direct, and academic publications. Signi�cant data were rigorously extracted and reported as per the PRISMA statement guideline. Individuals' risk from consuming raw milk was examined in 15 studies. According to a laboratory investigation report, raw milk contained several parasites and harmful bacteria in unpasteurized milk. These include campylobacteriosis, brucellosis, Staphylococcus aureus, streptococcus, salmonellosis, E. coli 0157, and other hazardous poisons like A�atoxin M1. People are exposed to pathogenic microorganisms, parasites, and other dangerous toxic agents while consuming raw milk. Therefore, ensuring the safety and quality of raw milk through implementing hazard-critical control points during production and distribution is mandatory in the dairy industry to safeguard general public health.


I N T R O D U C T I O N
Unpasteurized milk consumption is common throughout the globe, despite the negative consequence for consumer health. This review paper identi ed public health risks resulting from unpasteurized milk. Several keywords were used to search online, including Google Scholar, PubMed, Science Direct, and academic publications. Signi cant data were rigorously extracted and reported as per the PRISMA statement guideline. Individuals' risk from consuming raw milk was examined in 15 studies. According to a laboratory investigation report, raw milk contained several parasites and harmful bacteria in unpasteurized milk. These include campylobacteriosis, brucellosis, Staphylococcus aureus, streptococcus, salmonellosis, E. coli 0157, and other hazardous poisons like A atoxin M1. People are exposed to pathogenic microorganisms, parasites, and other dangerous toxic agents while consuming raw milk. Therefore, ensuring the safety and quality of raw milk through implementing hazard-critical control points during production and distribution is mandatory in the dairy industry to safeguard general public health.
sheep, cows, and camels; these might be different from one country to another based on religious and cultural ground [3]. Certain nutrients and mineral contents in milk provided for a human to acquire extraordinary good health conditions, including; calcium, phosphorus, Ribo avin (B2), vitamin B12,potassium,vitamin A,zinc,. Unfortunately, raw milk consumption could potentially cause several diseases for consumers. Since, milk and its products are the kind of perishable food that holds many essential nutrients, which is sensitive to microbial (pathogenic organisms) [7][8]. Some diseases are contagious diseases that spread out from animals to humans. It is estimated that approximately 75% of recently emerging infectious diseases, that affect human diseases were of animal origin; approximately 60% of all human pathogens are zoonotic [9-10]. Potential risk factors were milk handlers and animal's health conditions because, people exposed with certain pathogen via of direct contact with infected animals [1,11]. In many countries milk born outbreak were reported [12] and identi ed factors including milk handling, knowledge and environmental condition [9,13]. Safety and hygiene of milk problems were majorly affected due to lack of policy implementation, and inadequate infrastructure (agro-processing). which were key issues exacerbating risk to their health [6,14,15]. As evidence suggested that, milk borne disease mainly caused by consuming unprocessed milk [4,[16][17][18][19]19]. Ideally, ordinary people believed that drinking milk as a raw condition saved nutritional value, which overlooking its safety and hygienic condition [20][21][22][23]. Studies showed that young and elders, pregnant women, and chronic and complicated health illness individuals are highly risk groups for zoonotic disease [1,3,19,24], this was con rmed that their level of immunity systems and other dietary pattern. For example, milk products, such as cream, cheese, and yogurt can be easily contaminated with harmful bacteria and cause serious infections, including Brucellosis, Campylobacteriosis, E. coli 0157:H, Salmonella, and Toxoplasmosis. Unlikely, certain microbes such as Staphylococcus aureus and E. coli 0157:H7 are present in human and animal health, but cause serious illness and death occurs unless taken any medical treatment [25].

Milk borne disease Brucellosis
Brucella is a bacterial microbe that originates in unpasteurized dairy products. Brucella infection, or Brucellosis, has also been called "Undulant Fever" because of the regular recurrence of fever associated with the disease. It is one of the possible causes of lengthy fever with unknown origin in children [9,26,27].

Campylobacteriosis
The bacteria are typically detected in the feces of infected animals and food products that have come into contact with the germs during processing or preparation. One of the main causes of human infection is consuming unpasteurized milk. Campylobacter spp., including C. jejuni and C. coli, are the leading causes of enteritis in humans. Patient with disease may experience symptoms such as diarrhea, fever, nausea, vomiting, headaches, and muscle discomfort [13]. Cryptosporidiosis A coccidian parasite is known as Cryptosporidium species, which is carried by infected animals. People may expose with the disease due to consumption of unpasteurized milk and poor hand hygiene. Symptoms such as stomach pain, watery diarrhea, nausea, lack of appetite, vomiting, fever, and muscle pain were common [12,25,28].

Escherichia coli O157:H7 (E. coli) infection
Escherichia coli (E. coli) are a group of bacteria that inhabit the digestive tracts of both humans and animals. While majority of Escherichia coli are a natural component of the intestinal ora, some serotypes, like E. coli O157:H7 can cause intestinal disease (food poisoning) in humans, resulting in bloody diarrhea, hemolytic uremic syndrome (HUS), kidney failure [1,14,19,29]. Listeriosis Listeria monocytogenes are bacterial disease that attacks ruminants and humans. It is excreted via feces. Unlike other bacteria, people who touch sick animals might be at risk of getting the disease. Pregnant women and immunesuppressed individuals need to refuse to consume unpasteurized dairy products [3,30]. Salmonella Salmonellosis is a bacterial pathogen that is well-known for causing food-borne illnesses in humans. It is transmitted through eating and drinking improper or undercooked foods such as unpasteurized milk and dairy products, meat, eggs, and other animal products. Diseases with salmonellosis were including, feel abdominal discomfort, headache, fever, and diarrhea [19,31].

Sarcocystosis
The parasitic protozoan species known as Sarcocystis are found in unpasteurized milk. People got the disease through ingestion of the protozoan, most frequently undercooked and unsafe storage of animal products. Muscle tightness or painful swelling, weakness, headache, coughing, and temporary itching and rashes were some of the symptoms of the sarcocystosis-related disease, and symptoms such as fever, chills, sweating, chills, abdominal pain, diarrhea, nausea, and vomiting [25,28,32]. Toxoplasmosis Toxoplasma gondii is a tiny protozoan parasite that causes severe human disease. Individuals may manifest in the symptoms such as fever, body aches, headaches, and sore

M E T H O D S
Copyright (c) 2022. PJHS, Published by Crosslinks International Publishers throats). It is causing a dangerous condition for women during baby carriage [33,34].

Control of milk-born disease
Raw milk is the most known for perishability and cause serious disease for consumers unless keep and follow safety protocol, which is recommended by the world health organization including; Hazard Analysis Critical Control Point (HACCP) and other quality cheek parameters to control against physical, chemical and biological hazard [7,20,22]. Implementing adequate control strategies assures quality and safe milk production through pasteurization and "Test and Hold" programs [6,14].
Ottawa Scale (NOS) quality assessment protocol for a cross-sectional study [37].

PJHS VOL. 3 Issue. 4 September 2022
This systematic review paper was developed using PRISM guideline [35]. Different searching electronic data based were used; these included Google Scholar, PubMed, Science Direct, and other academic papers from different university depository to identify the relevant papers on public health threats with consumption of unpasteurized milk. In addition, keywords such as "foodborne", "Milk borne", "Raw milk", "unpasteurized milk", "consumption" "children", "elder ", "women", "Human health", "risk factors", "milk handling", "milk-borne outbreak", and "prevention and control" were used and connected by using "OR" and "AND" to nd more relevant papers, Furthermore, different studies were found out through cited reference list from all research papers. To develop this systematic review paper, pertinent studies were gathered. Experimental and epidemiologic investigations were included. Studies published in 2008-2022 reported pathogens related to the consumption of unpasteurized milk were addressed. Studies that were conducted before 2008 and investigated qualitatively were excluded from the review. Moreover, the corresponding authors were contacted through email whenever there were no full text available, and unanswered emails were excluded from the study. The outcome of the study was an isolated pathogen in raw milk and its effects on human health. Systematically data was extracted from the paper pre-designed format in the table and exported to all papers in the Medline reference database. The extraction process was adapted from the Joanna Briggs Institute (JBI) extraction format [36]. Relevant information was compiled in Microsoft Excel sheets by author and year, sample size, study design, region, milk-borne disease, and handling practice. The extracted format was developed based on the systematic objective of this study, and all authors participated to review independently the full text whenever disagreement happens between us resolved through discussion. The assessment of methodological quality, comparability, and outcome of each study was reviewed by all authors independently and using Newcastle

R E S U L T S
This systematic review paper addressed the public health threat of consuming unpasteurized milk, and its implication to prevent milk-borne disease. Fifteen studies systematically identi ed and extracted valuable information regarding topic desire. The overall undertaken procedure performed to reach the nal eligible paper was showed below in Fig1.

Identi cation
Records identi ed from electronic data based: Registers (n= 250) Records removed before screening: Duplicate records removed (n= 60) Records removed due to unreachable full papers ( n= 30)

Records Screened (n=140)
Records excluded year of publication and full papers (n=30) Reports sought for retrieval (n=105) Reports not retrieved (n=40)

Reports assessed for eligibility (n=65)
Reports excluded: -The nding not speci c (general food bome disease) (n=35) -Zoo notice disease results from other than milk bome (n=15)

Identi cation
Studies included in review (n=65) Reports of included studies (n=15)

Characteristics of reviewed studies
This paper included fteen pieces of research that were done in various nations throughout the world and released in late 2008. Most of the included studies were experimental or observational. As per researcher reports, the study tried to analyze their ndings and forward the message regarding the public health threat of consuming unpasteurized milk Table 1

D I S C U S S I O N
The nding of this systematic review found that signi cant results were provided with a review of fteen papers. Raw milk consumed children were 2.21 times and 1.14 times more likely to acquire campylobacteriosis and hemolytic uremic syndrome than their counterparts [13]. Brucellosis occurred in 41.4 out of every 100,000 people. Among the participants, 170 patients (37 percent) had direct exposure to domestic animals, while 103 cases (22.4%) had a history of consuming raw milk products [9]. Similarly, 50% of investigated children consumed raw camel milk and con rmed brucellosis [26]. Another study found that among 300 patients, brucellosis was reported (OR = 7.55, p = 0.0001), of which unpasteurized dairy consumers were 3.7 times more likely than non-cased [27]. Moreover, the study found that unpasteurized milk consumers showed Toxoplasma Gondi in the specimen, which result in negative pregnancy outcomes [33]. The review study also found that 179 food-borne outbreaks were reported, and approved that unpasteurized milk was dominant to cause outbreaks, 2276 individuals were affected by numerous milk-borne The Other studies also investigated and reported the epidemiological condition and distribution worldwide. People were seriously affected many times due to the direct consumption of unpasteurized milk. [13]

Author Participants Total sample Finding
Child 378 Campylobacteriosis cases of 2.12 and 1.14 and HUS cases of 0.02 and 0.09 were found in age 0-to 5-year, while 0.1 and 0.5 HUS in 5-year age group.
[10] All age group 480 Among the respondents, 48 consumers self-report human TB case history [9] Children <15 years 721 Brucellosis infections cases had detected 103 (22.4%) with a history of consuming raw milk products.
[26] Children 15 Brucella melitensis were positive in 50% of the children.
[31] All age groups There were 179 food-borne outbreaks were reported of which 2276 individuals were sick and one death.  [31]. Another study also found that among 480 study participants consumed raw milk, of which forty-eight manifested TB case histor y [10]. Another study investigated through prospective cohort design to nd out that manifestation of cancer cases was observed among raw milk consumers [38]. Serraino et al. (2019), estimated that fractions of (Hepatocarcinoma)HCC incidences attributable to the AFM1 intakes were 0.005 and 0.004 cases per 100,000 individuals in the 0-0.9 and 1-2.9-year age groups, respectively, and below 0.004 cases in the other age categories [39]. Similarly, laborator y investigation results found that raw milk contains A atoxin M1, which is the most toxin in the body and results in hepatocarcinoma for human health [16]. Different studies found that E.coli, Klebsiella, pneumonia, Staphylococcus aureus, and coagulase-negative staphylococcus were commonly presented in unpasteurized milk results poor food handlers and animals' health status [1,11,14]. Similarly, sorbitol-fermenting E.coli 0157 and Aeromonas hydrophila are also found in unpasteurized milk and its products [19,29].

C O N C L U S I O N
This review paper found that raw or unpasteurized milk contains pathogenic microorganisms and parasitic infections including; campylobacteriosis, salmonellosis, brucellosis, Staphylococcus aureus, streptococcus, E.coli 0157, Toxoplasmosis, and A atoxin M1, which might cause life-threatening condition even death for consumers. Particularly, toddlers, children, pregnant mothers, and other immune-surprised individuals were highly susceptible and seriously affect their health.

C o n  i c t s o f I n t e r e s t
The authors declare no con ict of interest.

S o u r c e o f F u n d i n g
The author(s) received no nancial support for the research, authorship and/or publication of this article