Epidemiology: A Very Short Introduction

Very Short Introductions #224

by Rodolfo Saracci

Epidemiology plays an all-important role in many areas of medicine, from discovering the relationship between tobacco smoking and lung cancer, to documenting the impact of diet, the environment, and exercise on general health, to tracking the origin and spread of new epidemics such as Swine Flu. It is truly a vital field, central to the health of society, but it is often poorly understood, largely due to misrepresentations in the media. In this Very Short Introduction, an internationally recognized authority on epidemiology, Dr. Rodolfo Saracci, provides a wealth of information on this key field, dispelling some of the myths surrounding the study of epidemiology, and explaining what epidemiology is and how vital it is to the discovery, control, and prevention of disease in world populations. Dr. Saracci provides a general explanation of the principles behind clinical trials, and explains the nature of basic statistics concerning disease. He also looks at the ethical and political issues related to obtaining and using information concerning patients, and trials involving placebos.

Genres: Science, Nonfiction, Medicine, Health, Biology, Medical, History

171 pages, ebook

First published April 5, 2010

About the author

Rodolfo Saracci has been Director of the European Educational Program in Epidemiology and visiting professor in the Universities of Aarhus and Montreal. He held lead positions in epidemiology at the International Agency for Research on Cancer in Lyon and with the Italian National Research Council in Pisa. He is a former president of the International Epidemiological Association.

Reviews

[Petra X · Rating 3 out of 5]

Epidemiology is the health of populations expressed as statistics. These statistics then suggest treatments, causative mechanisms of disease, and ways in which health care organisations can plan for the future. There you have it. "Epidemiology: An Introduction in Two Sentences."

On reading the book: I've just read one of the saddest things imaginable. Very young women, aged 15 to 22, were getting and sometimes dying from vaginal cancer. The research found the cause. All their mothers had been taking a drug to help prevent yet another miscarriage. Imagine going through many miscarriages and finally getting a drug that enabled you to carry your baby to full term and then 15 or so years later you find your daughter has a life-threatening at the worst, life-changing at the best, cancer caused by that drug and will never have babies of her own?

The book is really great for those that don't count sheep trying to go to sleep but instead lie there thinking up large surveys to track the sheep and people's sleep through years in the hope of finding that the probability of going to sleep counting sheep is more than 45% greater than if you didn't count sheep. But -5% compared to having a cup of cocoa and -25% than those who had a couple of tots of whisky. And then analysing the statistics to find that it might not have been the sheep as much as the way they jumped or the way you counted and whether those who had a mug rather than cup of cocoa went to sleep first and so on... and on.... (are you asleep yet?)

Dry like the Sahara in the second year of a drought.

[Lamia Al-Qahtani · Rating 3 out of 5]

أحب سلسلة مقدمة قصيرة جدا والمواضيع التي يتم اختيارها ولكن علم الأوبئة رغم وضوح الشرح والتقديم إلا أنه متصل اتصالا وثيقا بالإحصاء وأنا لا أحب العمليات الإحصائية لذلك أخذ الكتاب مني وقتا في الفهم وإعادة القراءة.

[Duaa Issa · Rating 4 out of 5]

فيه كتير أشياء استفدت منها.. الترجمة منيحة والكتاب مش بحاجة لكتير وقت بالقراءة..
تقريبا ما كنت بعرف شي عن علم الأوبئة بس ما اتغلبت بقراءتو.. فيه شغلات ما افهمتها.. بس بالمجمل بنصح فيه..

[The Conspiracy is Capitalism · Rating 2 out of 5]

The Good:
--Covers the fundamentals of epidemiology, the study of the health/disease (determinants and distributions) in populations (as opposed to doctors working primarily on the individual level, i.e. their patient...)
--An aside: the population perspective really draws me to public health, as this starts to get into questions of social values and structures, into political economy. While it seems many in the healthcare field have the heart for social care but are too compartmentalized in their technical fields to readily diagnose systemic root causes, this field is an obvious place to build solidarity.
--Always enjoy the use of historical examples when explaining concepts, as their applicability breathes life into the technical details while you learn some history on the side.

The Bad:
--Key technical components of epidemiology are research methodologies and statistics. While the former was explained well enough, this writing format was not optimal for statistics…
--The writing wasn’t bad, but one of my favorite writers happens to be an epidemiologist; so, this book with its mostly textbook style was a snoozer by comparison. Meanwhile, Ben Goldacre presents a much more critical and compelling narrative of public health and its challenges in the messy world of power, profit, and irrationality:
-Bad Science: Quacks, Hacks, and Big Pharma Flacks
-Bad Pharma: How Drug Companies Mislead Doctors and Harm Patients
-I Think You'll Find it's a Bit More Complicated Than That (collected articles, a real treat!)

[Mirjam · Rating 4 out of 5]

I think this is a very good introduction if you’re new to epidemiology. It was a lot of repeated knowledge for me, but I would have been disappointed in myself if it hadn’t been 😉

[Frank]

It turns out that epidemiology is mostly statistics.
Who knew?

No need for me to seek out advice on basic probability when there are lots of other things I could be learning.

[سمر محمد · Rating 3 out of 5]

(21/2016)

هذا الكتاب هو العدد 224 من سلسلة مقدمة قصيرة جدًا، وهي سلسلة من مطبعة جامعة أكسفورد تصدر منذ 1995. كتب صغيرة الحجم نسبيًا كبيرة المحتوى، يمكنك من خلالها التعرف على الكثير من المجالات المختلفة بسهولة ودون تعقيد مهما كانت صعوبة المجال، او لأنك لأول مرة تقرأ فيه، فهي تستهدف الجميع مهما كانت التخصصات ويقدمها متخصصين في مجالاتهم، وقد قامت مؤسسة هنداوي بترجمتها وتوفيرالكثر من اعدادها باللغة العربية
في هذا الكتاب يقوم الكاتب رودولفو ساراتشي وهو من رواد علم الأوبئة بمحاولة لتقريب هذا العلم لعامة الناس فالكثيرين لا يعرفون ما هو
الكتاب مكون من 10 فصول تفاوتت سهولتها وصعوبتها بالنسبة لي وخاصة في الفصول التي كانت مرتبطة بالإحصاء والمعادلات لبعدي عن هذا التخصص تمامًا، وعلى الرغم من ذلك كان واضحًا المعنى العام المراد توصيله
عرض من خلال الفصول تعريف لعلم الاوبئة ومحاولة للتفرقة بينه وبين علم الطب الحيوي وبعض العلوم التي قد تختلط بعلم الاوبئة في اذهان الناس كما عرض تاريخ علم الأوبئة والذي يرجع لأكثر من ألفي عام وكيف تطور مع الوقت حتى وصل إلى علم الاوبئة المعاصر، ويكمل المؤلف طريقه بعرض العديد من طرق البحث في هذا العلم مع امثلة توضحها
قبل ان اقرا الكتاب كنت ممن فهموا علم الاوبئة بطريقة خاطئة وانه متخصص في محاربة الاوبئة التي تظهر شرسة لتقضي على الانسان ولكن من ناحية دراسة الفيروسات ذاتها واكتشاف العلاج واللقاحات المناسبة للوقاية، ولكن اتضح خطأ هذا المفهوم فهو العلم المتخصص بدراسات وبائية عن مرض ما في مجتمع معين تساعد في معرفة انتشاره ومعدلاته خطورته، ليقدم تلك الدراسات لمن يهمه الأمر، بمعنى انه جزء من كل
كما كنت أظن انه متخصص في الامراض الخطيرة التي تظهر فجأة كـ "الإيبولا" وغيرها، ولكن الامثلة التي تم اضافتها اتضح ليّ انه مهتم بكل الأمراض، كمرض السكر والامرض القلبية وغيرها
هذا الكتاب رغم عدم فهمي الكامل للأجزاء الاحصائية فيه الا انه امدني ببعض المعلومات عن هذا العلم المجهول، ولايزال عندي الفضول للمزيد عنه ولكنه يعتبر بداية جيدة


1 / 11 / 2016

[Bojan Tunguz · Rating 4 out of 5]

Epidemiology is the study of factors affecting the health and illness of populations. However, the purpose of the epidemiology is not just the passive study of those illnesses from a purely intellectual viewpoint, but rather coming up with strategies and means of preventing and controlling the disease outbreaks. Furthermore, it is not necessary for those diseases to be microbial in nature. Cancer, heart disease, and even things like obesity fall under the purview of epidemiology.

This very short introduction deals with all major aspects of epidemiology. Its modern approach is up to date and the book does not fail to mention some of the recent headline-grabbing viral epidemics, like SARS and H1N1 ("swine flu"). The book pays detailed attention to the methodology of good epidemiological research, and tries to explain it in an accessible and readable way. There are numerous interesting and detailed graphs and charts throughout the book, but the book does not assume a high level of technical knowledge. It can be used as an introductory text to the vast epidemiological literature, or as a concise refresher of some key concepts. It can also serve as a useful reference book.

[عبد الرحمان · Rating 4 out of 5]

أعجبني أن أقرأ كتابا عن علم في تخصصي درسته بلغة أجنبية ولم أدرسه من قبل بالعربية، كانت متعة جديدة فعلا، أعجبني كذلك ترتيب الفصول الذي وُفق فيه الكاتب بشكل كبير وغطى كل ما يتعلق بعلم الأوبئة من تاريخه حتى أخلاقياته وعلاقته بالاقتصاد وفروع أخرى. ما لم يعجبني هو التعقيد في الأمثلة والمصطلحات في بعض فصول الكتاب والتي قد تشوش على القارئ العادي غير المتخصص والذي يُعتبر الكتاب موجها لهم بالأساس ما قد يجانب الهدف الرئيسي للكتاب، يحتاج قراءة متأنية ومتكررة لفهمه بشكل جيد.

[Faisal Almoaiqel · Rating 3 out of 5]

مقدمة قصيرة حول علم الأوبئة ..
احتجت فترة حتى أربط بين المصطلحات المذكورة في الكتاب ، والمصطلحات في الانقليزية في رأسي ..
مثير دور علم الأوبئة الأساس في باقي العلوم ..

[AhMâd Rêfâi · Rating 4 out of 5]

نشكر مؤسسة هندواي علي المجهود العظيم في الترجمة وعرضها الكتب العربية مجاناً للجميع ♥♥
https://www.hindawi.org/books/41724208/

[Vysh · Rating 3 out of 5]

i learned like three things but that’s because i took a four month break in the middle

[Cav · Rating 2 out of 5]

Epidemiology: A Very Short Introduction was an OK, albeit fairly dry look into the topic, that unfortunately left quite a bit to be desired.

Author Rodolfo Saracci is Honorary Director of research in epidemiology with the Italian National Research Council and Adjunct Professor of Epidemiology at the University of Arhus, Denmark. He holds postgraduate diplomas in internal medicine and medical statistics.

Rodolfo Saracci:


The book opens with a definition of epidemiology. Epidemiology owes its name to `epidemic', derived from the Greek epi (on) and demos (population). Basically, epidemiology is the study of disease(s) in the population.
Saracci also gives the reader a very brief history of this field, mentioning John Snow, cholera, and the famous Broad Street pump.

Saracci provides this outline:

"All aspects of health when studied at the level of population are the proper domain of epidemiology, which covers not only the description of how diseases and, more generally, health-related conditions occur in the population, but also the search for the factors, as a rule multiple, at their origin. This investigative activity is sustained by scientific curiosity but is firmly directed towards an applied objective: the prevention and treatment of disease and promotion of health. A fascinating and challenging feature of epidemiology is that it explores health and disease in connection with factors which, to take heart attacks as an example, span from the level of the molecule, say blood cholesterol, to the level of society, say loss of employment. This broad perspective makes epidemiology at the same time a biomedical and a social science. Epidemiological studies include both routine applications of epidemiological methods, for example in surveillance of communicable diseases or in monitoring of hospital admissions and discharges, and research investigations designed to generate new knowledge of general relevance."

Unfortuntely, most of the writing here is very dry and unengaging. Saracci quickly gets into some technical material, and proceeds to rattle off some rather robotic prose. Ratios, rates, charts, "confidence limits", and other technical metrics are introduced by Saracci in a flat and methodical fashion. The writing continues like this for the duration.
I really dislike books written in this fashion, and I always penalize them for it.


***********************

Although the field of epidemiology is an interesting one, the writing in this book left much to be desired for me. Saracci's writing epitomizes everything I dislike about science books. It is presented in a dry, flat, and unengaging tone; similar to an academic textbook.
I have read quite a few offerings from the "Very Short Introduction" series, and I would place this one near the bottom of the list.
2 stars.

[Chris Esposo · Rating 3 out of 5]

Not a bad introduction to epidemiology (at least from the perspective of a non-epidemiologist). Given the current news, at the very least, a "short introduction" to subject has now become a necessity for the average citizen to understand, to at help wade through the plethora of information that is being bombarded to them via media and other sources. This book hits the spot for that use-case, as well as a more specialized use-case focused for an introductory data scientist, who may profit from a short introduction the field, which will double as an introduction to experimentation and it's associated design, as well as very basic statistical reasoning.

This use-case works so well because in a true sense, epidemiology, and other subfields within the biological/medical sciences, like population genetics, and bioinformatics, actually inform the nature and development of data science in it's first decade of existence by virtue of the fact that many people in these subject-matters transitioned over to the profession seeking more lucrative (and exciting) work. One can see this most directly, in the nature of experimentation with respect to web-traffic, and how this problem-setup had traditionally been contextualized almost as a 1:1 port from epidemiological experimentation.

The book itself is a clean introduction to these notions, with material taken mostly from the methodological area vs. the medical/genetics domains. Use-cases or data presented are mostly generic tabular data that require no knowledge of medicine/biology etc., and the analysis/methods introduced could really be taken from any use-case in almost any domain that dealt with samples of populations.

That being said, all of the essentials are here, from a short intro to randomized control trials, dealing with populations, and how one may aggregate individual-level data to a higher-level unit, and what parameters one may extract from that process to run statistical analysis and/or experimentation, correlation, conditions of causation (from the classical standpoint), survival analysis, study of cohorts, experimentation, and meta analysis.

Most of these short-introduction books have been poor, yet I find this topic to be the perfect mix of intellectual rigor and common-day relevance to make this summary very good to both the general and purpose-driven reader. For the general reader, I think they will be well-equipped to look at contemporary news articles on the nature of Covid-19 (or any future pandemic) with a more informed critical eye, and the topics mentioned here easily extend to more formal text on the material and/or a introduction to statistics textbook. Recommended.

[Kam Yung Soh · Rating 4 out of 5]

A good introduction to the topic of Epidemiology: what it is, what it does and how does society benefit from it. You will get a good idea of how epidemiology works and how it benefits society by informing public health and keeping people healthy.

The book starts with the history of epidemiology and how it can determine the causes of diseases and epidemics in early history, even though the causes of diseases were not yet known. The book then goes into how epidemiology uses statistics and other tools to measure the health of people.

Other chapters describe how epidemiology is used to search for the cause of a disease, establishing the cause of it and how to control a disease. Various examples, like cancer caused by smoking, the human papillomavirus, diabeties, etc. are used to show how epidemiology is used.

Finally, several chapters are used to show how epidemiology is used to examine the health of the public in general. Several challenges to epidemiology in the form of genetic consent and storage of samples for future studies are also highlighted.

[Ninja · Rating 4 out of 5]

A really good intro to epidemiology, which as it states at the start is the study of health and disease generally in populations.
After a brief 3 or so pages on the history of epidemiology, it moves heavy on the numbers and stats at the start that are involved in performing studies and determining results, before opening to broader discussion in the latter part. 36% of births go unregistered, deaths are not always well captured, disease registries (eg for cancers) vary by countries and regions. And of course these stats just capture averages which means countries specifically will swing well higher or lower.
The book was written a decade ago, in 2010, during the midst of the GFC, which means the general world economic downturn factored into some comments (increasing global poverty) and of course being well before coronavirus (though H1N1 gets some mention, which would have been quite topical at the time).

[hamdy boghdady · Rating 5 out of 5]

لابد أن نقرأ حتى ننجو، ويقول مارك كيوبان‏ "أقرأ لساعات وبشكل يومي لأجد فكرة واحدة تساعدني أجعل حياتي أفضل".

في البداية أعجبني ثناء الكاتب على اللغة العربية، واعترافه الحقيقي، والذي قلّما نجده من العلماء والكُتّاب الغربيين عن فضل العرب، ولو حتى قديمًا!

يعتبر الكتاب تسليط ضوء على بعض المفاهيم الخاصة بعلم الأوبئة، مدللا كلامه باحصائيات وبعض الطرق لحساب انتشار الأمراض والعدوى إلخ.
ويتنقل لبعض التواريخ والأوبئة المختلفة.
حتى ينتهي بالفصل الأخير، وعن مدى ارتباط علم الأوبئة بالصحة العامة، وأهميته.

كتاب جيد، استفدت منه، وبه الكثير المعلومات المفيدة، وطرق لحساب بعض الأوبئة،وكيفية الاحصائيات للأمراض والعدوى.

[Victor Sonkin · Rating 2 out of 5]

The book gives you a general idea of what epidemiology is and how it is different from other medical specializations, but it is extremely boring; knowing that VSI vary greatly in this respect, this is one of the worst examples.

[عمر الحمادي · Rating 3 out of 5]

كتاب جيد لمعرفة المفيد من علم الأوبئة وكيفية دراستها وتحليلها.

[عدنان عوض · Rating 3 out of 5]

أول تجربة لي مع الكتاب المسموع من تطبيق Audible، وثاني قراءة لي لسلسلة A Very Short Introduction...

بالمجمل لم تعجبني تقسيمات ومحتويات الكتاب. ما توقعته هو كتاب يحوي المحاور الأساسية في علمالأوبئة لا أن يتناول في عدد من فصوله تطبيقات لبعض المعادلات الخاصة ببعض الحسابات...

هو مقدمة عادية ولا أراها كافية في الموضوع.

بالنسبة لتجربة الكتاب المسموع فمبدئياً أقول أنها جيدة خصوصاً في الموضوعات التي تحتاج لمعلومات عامة فيها لا لتدقيق كبير. لا أرى أنه وسيلة لتقضية الوقت في أوقات الازدحام والانشغال مثلاً، فالاستماع يحتاج لتفرُّغ وتركيز وهذا يأخذ زمن وجهد كالكتاب الورقي.

[Abrar · Rating 3 out of 5]

A shorten version of basic information in epidemiology. This book is a very good introductory of principles and calculations as prevalence, incidence...etc. and provides a simple examples. However, some specific sections require further reading from other books and articles.

[إيمان محمودي · Rating 3 out of 5]

💠كتابنا اليوم (علم الأوبئة) مقدمة قصيرة جدا للكاتب رودولفو سارتشي.

يقدم لنا الكاتب في هذا الكتاب مدخل موجز لعلم الأوبئة من خلال مفاهيمه الأساسية، أدواته، أهميته في الصحة العامة، وكيف يُستخدم في البحث واتخاذ القرارات الصحية والسياسات.

يتميز الكتاب في تبسيط مفاهيم معقدة في علم الأوبئة، مثل حساسية خصوصية الاختبارات والمخاطر النسبية وتأثير التغاير،وغيرها لذلك هو مدخل جيد لمن لم يدرس الأوبئة من قبل.

وبالرغم كونه قصيرًا إلا أنني اعتقد أنه غطى معظم المفاهيم الأساسية التي ينبغي أن يعرفها القارئ الراغب في فهم كيف يُجرى البحث الوبائي ولماذا هو مهم في الصحة العامة.

والجميل أنه قدم أمثلة واقعية وتطبيقات لكيف يُستخدم علم الأوبئة في تتبّع الأمراض، تحليل البيانات، اتخاذ القرارات في الأزمات الصحية (مثل تفشي الأمراض).


وركز على الالتباسات والمفاهيم الخاطئة التي من شأنها أن تعرّف القارئ بالمخاطر التي قد تقع في تفسير نتائج الدراسات، مثل التحييز، التداخل، القيود المنهجية، وغيرها وهذا يساعد في أن يكون القارئ ناقدًا، لا متلقّيًا فقط.

رقم صغر حجم الكتاب نسبيا إلا إن سرده واضح وسلس وأرى أنه كتاب جيد وأنصح بقرائته لمن يبحث عن مدخل جيد وميسر لعلم الأوبئة الذي يُعطيك الأساس الجيد لتبني عليه لاحقًا أطروحة دراسية أو بحثية.

تقييمي 7/10
قراءة ممتعة
إيمان محمودي

[Abdulsattar Ashour · Rating 4 out of 5]

It was a good brief about a very important science field, especially while we're living with a global, fatal and easily-transmitted pandemic and epidemiologists besides all the healthcare workers have the upper hand in controlling the situation. I've been always fascinated by community and public health medicine, how we can manage hundreds of diseases that form a heavy burden, tracking of new cases, researching, vaccinations, statistics that suggest treatments, causative mechanisms of disease, and ways in which healthcare settings can plan for the future.. From observational studies to experimental ones, Epidemiology has showed us how complex and greatly important for global health it is. My clinical research course in medical school has made me deeply familiar with all of this content, but this book was really a good addition specifically because it focused on some ethical dilemmas and how advancing justice in health by minimizing health inequalities within and between developed and developing countries is needed.. Thanks Dr. Rodolfo.

[Ben Erentraut · Rating 5 out of 5]

I would thoroughly recommend this as an introductory text to any students taking classes in epidemiology. It takes concepts that, at first glance, seem very complicated, but breaks them down into the basic arithmetic which is all that is needed to calculate basic parameters such as prevalence and incidence. It also uses real life historical and made up examples to contextualise the concepts as well. This book is a good introduction to a subject that, whilst very dependent on mathematics and statistics, can be a very interesting study, with far reaching implications. I also enjoyed how it concluded with a chapter on the ethical aspects of epidemiology, as these are issues that are very important. If you're interested in the ethical side, you may also like:
- Medical ethics: A very short introduction, by Tony Hope
- The immortal life of Henrietta Lacks, By Rebecca Skloot
- Bad Science, by Ben Goldacre

[Dominika · Rating 4 out of 5]

I figured I'd get this book to prepare me for my future path, and felt that it introduced a lot of concepts concisely yet correctly. Epidemiology relies a lot on statistical analysis, and while this book doesn't go into the actual techniques, it does introduce the theory and applications pretty well. I was even surprised by how the book introduces the social and political aspects of healthcare. Epidemiology is a very large field and I fully expect this to be a supplement to some Lynda programming courses I'm taking, but it was cheap and worked well for what I wanted from it.

This is also the first book I've read in A Very Short Introduction series, and I'm pretty impressed. Admittedly, they are a very good size for carrying around (as opposed to the (blank) for Dummies books, which are huge).

[YJ · Rating 3 out of 5]

"Epidemiology is at heart a field of applied research with the improvement of the health of all as the key aim." (pg. 97)

I understand that Epidemiology is basically statistics/biostatistics but being a non-math person, it was really difficult (and a bit boring) to actually get past the first 8 chapters as it was key concepts explained through statistical examples. Personally, I found chapters 9 and 10 the most interesting and informational as it was talking about how epidemiology fits into the medical field and the ethics of epidemiological studies.

[Amos Tai · Rating 4 out of 5]

What’s a better time to read this when epidemiologists have become one of the sexiest professions out there? Jokes aside, I do have to work with some from time to time so it’s good to understand their language better. I particular like its concluding remark: “Advancing justice in health by minimizing health inequalities within and between countries is the common aim of all streams of epidemiology and the acid test of its value to health.”

[Selma Dja · Rating 2 out of 5]

علم الأوبئة" ل"رودولفو ساراتشي" هي مقدمة قصيرة يقدم فيها مدخل إلى عالم الأمراض الوبائية ويركز بصفة خاصة على البعد الإجتماعي والفيسيولوجي الصحة والمرض.
يستهل الكاتب كتابه بتعريف علم الأوبئة وتاريخه وتطور أبحاثه عبر الزمن بفضل الدراسات التجريبية لتصل إلى ما يسمى اليوم علم الأوبئة المعاصر. ثم يذكر أنواع الدراسات المستخدمة في علم الأوبئة د .
يختتم الكاتب كتابه بالتأكيد على ضرورة تضافر الجهود المجتمعية لتحسين الصحة من خلال الطب الإكلينيكي ، الوقاية والتشخيص المبكر وتجميع نتائج الأبحاث والدراسات الوبائية في سرية واستخدامها بحذر لاعتبارات أخلاقية وسياسية.
بما أن الكتاب يناقش موضوع علميا بحتا فقد كان أسلوب الكاتب تلقينيا، مباشرا ودقيقا في اختيار المصطلحات . وتوظيف الأمثلة والإستعانة بالمخططات والجداول
الإحصائية والرسومات البيانية كان موفقا بشكل كبير وساهم في توضيح الأفكار المطروحة.

[Maged M. · Rating 2 out of 5]

كتاب يقدم مقدمه مهمه لكل من يهتم بال bioinformatics
بالاضافة الى المعلومات القيمه عن كيفية انتشار الامراض وتحليل اسبابها

[عبدالله نمير · Rating 3 out of 5]

الكتابة العلمية على طريقة الحكايات